text: /*****************************************************************************
  
  Copyright (c) 2005, 2017, Oracle and/or its affiliates. All Rights Reserved.
  Copyright (c) 2014, 2018, MariaDB Corporation.
  
  This program is free software; you can redistribute it and/or modify it under
  the terms of the GNU General Public License as published by the Free Software
  Foundation; version 2 of the License.
  
  This program is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License along with
  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
  
  *****************************************************************************/
  
  /**************************************************//**
  @file row/row0merge.cc
  New index creation routines using a merge sort
  
  Created 12/4/2005 Jan Lindstrom
  Completed by Sunny Bains and Marko Makela
  *******************************************************/
  #include <my_global.h>
  #include <log.h>
  #include <sql_class.h>
  
  #include <math.h>
  
  #include "ha_prototypes.h"
  
  #include "row0merge.h"
  #include "row0ext.h"
  #include "row0log.h"
  #include "row0ins.h"
  #include "row0row.h"
  #include "row0sel.h"
  #include "log0crypt.h"
  #include "dict0crea.h"
  #include "trx0purge.h"
  #include "lock0lock.h"
  #include "pars0pars.h"
  #include "ut0sort.h"
  #include "row0ftsort.h"
  #include "row0import.h"
  #include "row0vers.h"
  #include "handler0alter.h"
  #include "btr0bulk.h"
  #include "fsp0sysspace.h"
  #include "ut0new.h"
  #include "ut0stage.h"
  #include "fil0crypt.h"
  
  float my_log2f(float n)
  {
  	/* log(n) / log(2) is log2. */
  	return (float)(log((double)n) / log((double)2));
  }
  
  /* Ignore posix_fadvise() on those platforms where it does not exist */
  #if defined _WIN32
  # define posix_fadvise(fd, offset, len, advice) /* nothing */
  #endif /* _WIN32 */
  
  /* Whether to disable file system cache */
  char	srv_disable_sort_file_cache;
  
  /** Class that caches index row tuples made from a single cluster
  index page scan, and then insert into corresponding index tree */
  class index_tuple_info_t {
  public:
  	/** constructor
  	@param[in]	heap	memory heap
  	@param[in]	index	index to be created */
  	index_tuple_info_t(
  		mem_heap_t*	heap,
  		dict_index_t*	index) UNIV_NOTHROW
  	{
  		m_heap = heap;
  		m_index = index;
  		m_dtuple_vec = UT_NEW_NOKEY(idx_tuple_vec());
  	}
  
  	/** destructor */
  	~index_tuple_info_t()
  	{
  		UT_DELETE(m_dtuple_vec);
  	}
  
  	/** Get the index object
  	@return the index object */
  	dict_index_t*   get_index() UNIV_NOTHROW
  	{
  		return(m_index);
  	}
  
  	/** Caches an index row into index tuple vector
  	@param[in]	row	table row
  	@param[in]	ext	externally stored column
  	prefixes, or NULL */
  	void add(
  		const dtuple_t*		row,
  		const row_ext_t*	ext) UNIV_NOTHROW
  	{
  		dtuple_t*	dtuple;
  
  		dtuple = row_build_index_entry(row, ext, m_index, m_heap);
  
  		ut_ad(dtuple);
  
  		m_dtuple_vec->push_back(dtuple);
  	}
  
  	/** Insert spatial index rows cached in vector into spatial index
  	@param[in]	trx_id		transaction id
  	@param[in,out]	row_heap	memory heap
  	@param[in]	pcur		cluster index scanning cursor
  	@param[in,out]	scan_mtr	mini-transaction for pcur
  	@param[out]	mtr_committed	whether scan_mtr got committed
  	@return DB_SUCCESS if successful, else error number */
  	dberr_t insert(
  		trx_id_t		trx_id,
  		mem_heap_t*		row_heap,
  		btr_pcur_t*		pcur,
  		mtr_t*			scan_mtr,
  		bool*			mtr_committed)
  	{
  		big_rec_t*      big_rec;
  		rec_t*          rec;
  		btr_cur_t       ins_cur;
  		mtr_t           mtr;
  		rtr_info_t      rtr_info;
  		ulint*		ins_offsets = NULL;
  		dberr_t		error = DB_SUCCESS;
  		dtuple_t*	dtuple;
  		ulint		count = 0;
  		const ulint	flag = BTR_NO_UNDO_LOG_FLAG
  				       | BTR_NO_LOCKING_FLAG
  				       | BTR_KEEP_SYS_FLAG | BTR_CREATE_FLAG;
  
  		ut_ad(dict_index_is_spatial(m_index));
  
  		DBUG_EXECUTE_IF("row_merge_instrument_log_check_flush",
  			log_sys.check_flush_or_checkpoint = true;
  		);
  
  		for (idx_tuple_vec::iterator it = m_dtuple_vec->begin();
  		     it != m_dtuple_vec->end();
  		     ++it) {
  			dtuple = *it;
  			ut_ad(dtuple);
  
  			if (log_sys.check_flush_or_checkpoint) {
  				if (!(*mtr_committed)) {
  					btr_pcur_move_to_prev_on_page(pcur);
  					btr_pcur_store_position(pcur, scan_mtr);
  					mtr_commit(scan_mtr);
  					*mtr_committed = true;
  				}
  
  				log_free_check();
  			}
  
  			mtr.start();
  			m_index->set_modified(mtr);
  
  			ins_cur.index = m_index;
  			rtr_init_rtr_info(&rtr_info, false, &ins_cur, m_index,
  					  false);
  			rtr_info_update_btr(&ins_cur, &rtr_info);
  
  			btr_cur_search_to_nth_level(m_index, 0, dtuple,
  						    PAGE_CUR_RTREE_INSERT,
  						    BTR_MODIFY_LEAF, &ins_cur,
  						    0, __FILE__, __LINE__,
  						    &mtr);
  
  			/* It need to update MBR in parent entry,
  			so change search mode to BTR_MODIFY_TREE */
  			if (rtr_info.mbr_adj) {
  				mtr_commit(&mtr);
  				rtr_clean_rtr_info(&rtr_info, true);
  				rtr_init_rtr_info(&rtr_info, false, &ins_cur,
  						  m_index, false);
  				rtr_info_update_btr(&ins_cur, &rtr_info);
  				mtr_start(&mtr);
  				m_index->set_modified(mtr);
  				btr_cur_search_to_nth_level(
  					m_index, 0, dtuple,
  					PAGE_CUR_RTREE_INSERT,
  					BTR_MODIFY_TREE, &ins_cur, 0,
  					__FILE__, __LINE__, &mtr);
  			}
  
  			error = btr_cur_optimistic_insert(
  				flag, &ins_cur, &ins_offsets, &row_heap,
  				dtuple, &rec, &big_rec, 0, NULL, &mtr);
  
  			if (error == DB_FAIL) {
  				ut_ad(!big_rec);
  				mtr.commit();
  				mtr.start();
  				m_index->set_modified(mtr);
  
  				rtr_clean_rtr_info(&rtr_info, true);
  				rtr_init_rtr_info(&rtr_info, false,
  						  &ins_cur, m_index, false);
  
  				rtr_info_update_btr(&ins_cur, &rtr_info);
  				btr_cur_search_to_nth_level(
  					m_index, 0, dtuple,
  					PAGE_CUR_RTREE_INSERT,
  					BTR_MODIFY_TREE,
  					&ins_cur, 0,
  					__FILE__, __LINE__, &mtr);
  
  
  				error = btr_cur_pessimistic_insert(
  						flag, &ins_cur, &ins_offsets,
  						&row_heap, dtuple, &rec,
  						&big_rec, 0, NULL, &mtr);
  			}
  
  			DBUG_EXECUTE_IF(
  				"row_merge_ins_spatial_fail",
  				error = DB_FAIL;
  			);
  
  			if (error == DB_SUCCESS) {
  				if (rtr_info.mbr_adj) {
  					error = rtr_ins_enlarge_mbr(
  							&ins_cur, &mtr);
  				}
  
  				if (error == DB_SUCCESS) {
  					page_update_max_trx_id(
  						btr_cur_get_block(&ins_cur),
  						btr_cur_get_page_zip(&ins_cur),
  						trx_id, &mtr);
  				}
  			}
  
  			mtr_commit(&mtr);
  
  			rtr_clean_rtr_info(&rtr_info, true);
  			count++;
  		}
  
  		m_dtuple_vec->clear();
  
  		return(error);
  	}
  
  private:
  	/** Cache index rows made from a cluster index scan. Usually
  	for rows on single cluster index page */
  	typedef std::vector<dtuple_t*, ut_allocator<dtuple_t*> >
  		idx_tuple_vec;
  
  	/** vector used to cache index rows made from cluster index scan */
  	idx_tuple_vec*		m_dtuple_vec;
  
  	/** the index being built */
  	dict_index_t*		m_index;
  
  	/** memory heap for creating index tuples */
  	mem_heap_t*		m_heap;
  };
  
  /* Maximum pending doc memory limit in bytes for a fts tokenization thread */
  #define FTS_PENDING_DOC_MEMORY_LIMIT	1000000
  
  /** Insert sorted data tuples to the index.
  @param[in]	index		index to be inserted
  @param[in]	old_table	old table
  @param[in]	fd		file descriptor
  @param[in,out]	block		file buffer
  @param[in]	row_buf		row_buf the sorted data tuples,
  or NULL if fd, block will be used instead
  @param[in,out]	btr_bulk	btr bulk instance
  @param[in,out]	stage		performance schema accounting object, used by
  ALTER TABLE. If not NULL stage->begin_phase_insert() will be called initially
  and then stage->inc() will be called for each record that is processed.
  @return DB_SUCCESS or error number */
  static	MY_ATTRIBUTE((warn_unused_result))
  dberr_t
  row_merge_insert_index_tuples(
  	dict_index_t*		index,
  	const dict_table_t*	old_table,
  	const pfs_os_file_t&	fd,
  	row_merge_block_t*	block,
  	const row_merge_buf_t*	row_buf,
  	BtrBulk*		btr_bulk,
  	const ib_uint64_t	table_total_rows, /*!< in: total rows of old table */
  	const double		pct_progress,	/*!< in: total progress
  						percent until now */
  	const double		pct_cost, /*!< in: current progress percent
  					  */
  	row_merge_block_t*	crypt_block, /*!< in: crypt buf or NULL */
  	ulint			space,	   /*!< in: space id */
  	ut_stage_alter_t*	stage = NULL);
  
  /******************************************************//**
  Encode an index record. */
  static MY_ATTRIBUTE((nonnull))
  void
  row_merge_buf_encode(
  /*=================*/
  	byte**			b,		/*!< in/out: pointer to
  						current end of output buffer */
  	const dict_index_t*	index,		/*!< in: index */
  	const mtuple_t*		entry,		/*!< in: index fields
  						of the record to encode */
  	ulint			n_fields)	/*!< in: number of fields
  						in the entry */
  {
  	ulint	size;
  	ulint	extra_size;
  
  	size = rec_get_converted_size_temp(
  		index, entry->fields, n_fields, &extra_size);
  	ut_ad(size >= extra_size);
  
  	/* Encode extra_size + 1 */
  	if (extra_size + 1 < 0x80) {
  		*(*b)++ = (byte) (extra_size + 1);
  	} else {
  		ut_ad((extra_size + 1) < 0x8000);
  		*(*b)++ = (byte) (0x80 | ((extra_size + 1) >> 8));
  		*(*b)++ = (byte) (extra_size + 1);
  	}
  
  	rec_convert_dtuple_to_temp(*b + extra_size, index,
  				   entry->fields, n_fields);
  
  	*b += size;
  }
  
  /******************************************************//**
  Allocate a sort buffer.
  @return own: sort buffer */
  static MY_ATTRIBUTE((malloc, nonnull))
  row_merge_buf_t*
  row_merge_buf_create_low(
  /*=====================*/
  	mem_heap_t*	heap,		/*!< in: heap where allocated */
  	dict_index_t*	index,		/*!< in: secondary index */
  	ulint		max_tuples,	/*!< in: maximum number of
  					data tuples */
  	ulint		buf_size)	/*!< in: size of the buffer,
  					in bytes */
  {
  	row_merge_buf_t*	buf;
  
  	ut_ad(max_tuples > 0);
  
  	ut_ad(max_tuples <= srv_sort_buf_size);
  
  	buf = static_cast<row_merge_buf_t*>(mem_heap_zalloc(heap, buf_size));
  	buf->heap = heap;
  	buf->index = index;
  	buf->max_tuples = max_tuples;
  	buf->tuples = static_cast<mtuple_t*>(
  		ut_malloc_nokey(2 * max_tuples * sizeof *buf->tuples));
  	buf->tmp_tuples = buf->tuples + max_tuples;
  
  	return(buf);
  }
  
  /******************************************************//**
  Allocate a sort buffer.
  @return own: sort buffer */
  row_merge_buf_t*
  row_merge_buf_create(
  /*=================*/
  	dict_index_t*	index)	/*!< in: secondary index */
  {
  	row_merge_buf_t*	buf;
  	ulint			max_tuples;
  	ulint			buf_size;
  	mem_heap_t*		heap;
  
  	max_tuples = srv_sort_buf_size
  		/ ut_max(static_cast<ulint>(1),
  			 dict_index_get_min_size(index));
  
  	buf_size = (sizeof *buf);
  
  	heap = mem_heap_create(buf_size);
  
  	buf = row_merge_buf_create_low(heap, index, max_tuples, buf_size);
  
  	return(buf);
  }
  
  /******************************************************//**
  Empty a sort buffer.
  @return sort buffer */
  row_merge_buf_t*
  row_merge_buf_empty(
  /*================*/
  	row_merge_buf_t*	buf)	/*!< in,own: sort buffer */
  {
  	ulint		buf_size	= sizeof *buf;
  	ulint		max_tuples	= buf->max_tuples;
  	mem_heap_t*	heap		= buf->heap;
  	dict_index_t*	index		= buf->index;
  	mtuple_t*	tuples		= buf->tuples;
  
  	mem_heap_empty(heap);
  
  	buf = static_cast<row_merge_buf_t*>(mem_heap_zalloc(heap, buf_size));
  	buf->heap = heap;
  	buf->index = index;
  	buf->max_tuples = max_tuples;
  	buf->tuples = tuples;
  	buf->tmp_tuples = buf->tuples + max_tuples;
  
  	return(buf);
  }
  
  /******************************************************//**
  Deallocate a sort buffer. */
  void
  row_merge_buf_free(
  /*===============*/
  	row_merge_buf_t*	buf)	/*!< in,own: sort buffer to be freed */
  {
  	ut_free(buf->tuples);
  	mem_heap_free(buf->heap);
  }
  
  /** Convert the field data from compact to redundant format.
  @param[in]	row_field	field to copy from
  @param[out]	field		field to copy to
  @param[in]	len		length of the field data
  @param[in]	zip_size	compressed BLOB page size,
  				zero for uncompressed BLOBs
  @param[in,out]	heap		memory heap where to allocate data when
  				converting to ROW_FORMAT=REDUNDANT, or NULL
  				when not to invoke
  				row_merge_buf_redundant_convert(). */
  static
  void
  row_merge_buf_redundant_convert(
  	const dfield_t*		row_field,
  	dfield_t*		field,
  	ulint			len,
  	const page_size_t&	page_size,
  	mem_heap_t*		heap)
  {
  	ut_ad(field->type.mbminlen == 1);
  	ut_ad(field->type.mbmaxlen > 1);
  
  	byte*		buf = (byte*) mem_heap_alloc(heap, len);
  	ulint		field_len = row_field->len;
  	ut_ad(field_len <= len);
  
  	if (row_field->ext) {
  		const byte*	field_data = static_cast<byte*>(
  			dfield_get_data(row_field));
  		ulint		ext_len;
  
  		ut_a(field_len >= BTR_EXTERN_FIELD_REF_SIZE);
  		ut_a(memcmp(field_data + field_len - BTR_EXTERN_FIELD_REF_SIZE,
  			    field_ref_zero, BTR_EXTERN_FIELD_REF_SIZE));
  
  		byte*	data = btr_copy_externally_stored_field(
  			&ext_len, field_data, page_size, field_len, heap);
  
  		ut_ad(ext_len < len);
  
  		memcpy(buf, data, ext_len);
  		field_len = ext_len;
  	} else {
  		memcpy(buf, row_field->data, field_len);
  	}
  
  	memset(buf + field_len, 0x20, len - field_len);
  
  	dfield_set_data(field, buf, len);
  }
  
  /** Insert a data tuple into a sort buffer.
  @param[in,out]	buf		sort buffer
  @param[in]	fts_index	fts index to be created
  @param[in]	old_table	original table
  @param[in]	new_table	new table
  @param[in,out]	psort_info	parallel sort info
  @param[in]	row		table row
  @param[in]	ext		cache of externally stored
  				column prefixes, or NULL
  @param[in,out]	doc_id		Doc ID if we are creating
  				FTS index
  @param[in,out]	conv_heap	memory heap where to allocate data when
  				converting to ROW_FORMAT=REDUNDANT, or NULL
  				when not to invoke
  				row_merge_buf_redundant_convert()
  @param[in,out]	err		set if error occurs
  @param[in,out]	v_heap		heap memory to process data for virtual column
  @param[in,out]	my_table	mysql table object
  @param[in]	trx		transaction object
  @return number of rows added, 0 if out of space */
  static
  ulint
  row_merge_buf_add(
  	row_merge_buf_t*	buf,
  	dict_index_t*		fts_index,
  	const dict_table_t*	old_table,
  	const dict_table_t*	new_table,
  	fts_psort_t*		psort_info,
  	const dtuple_t*		row,
  	const row_ext_t*	ext,
  	doc_id_t*		doc_id,
  	mem_heap_t*		conv_heap,
  	dberr_t*		err,
  	mem_heap_t**		v_heap,
  	TABLE*			my_table,
  	trx_t*			trx)
  {
  	ulint			i;
  	const dict_index_t*	index;
  	mtuple_t*		entry;
  	dfield_t*		field;
  	const dict_field_t*	ifield;
  	ulint			n_fields;
  	ulint			data_size;
  	ulint			extra_size;
  	ulint			bucket = 0;
  	doc_id_t		write_doc_id;
  	ulint			n_row_added = 0;
  	VCOL_STORAGE*		vcol_storage= 0;
  	byte*			record;
  	DBUG_ENTER("row_merge_buf_add");
  
  	if (buf->n_tuples >= buf->max_tuples) {
  		DBUG_RETURN(0);
  	}
  
  	DBUG_EXECUTE_IF(
  		"ib_row_merge_buf_add_two",
  		if (buf->n_tuples >= 2) DBUG_RETURN(0););
  
  	UNIV_PREFETCH_R(row->fields);
  
  	/* If we are building FTS index, buf->index points to
  	the 'fts_sort_idx', and real FTS index is stored in
  	fts_index */
  	index = (buf->index->type & DICT_FTS) ? fts_index : buf->index;
  
  	/* create spatial index should not come here */
  	ut_ad(!dict_index_is_spatial(index));
  
  	n_fields = dict_index_get_n_fields(index);
  
  	entry = &buf->tuples[buf->n_tuples];
  	field = entry->fields = static_cast<dfield_t*>(
  		mem_heap_alloc(buf->heap, n_fields * sizeof *entry->fields));
  
  	data_size = 0;
  	extra_size = UT_BITS_IN_BYTES(unsigned(index->n_nullable));
  
  	ifield = dict_index_get_nth_field(index, 0);
  
  	for (i = 0; i < n_fields; i++, field++, ifield++) {
  		ulint			len;
  		const dict_col_t*	col;
  		ulint			col_no;
  		ulint			fixed_len;
  		const dfield_t*		row_field;
  
  		col = ifield->col;
  		const dict_v_col_t*	v_col = NULL;
  		if (col->is_virtual()) {
  			v_col = reinterpret_cast<const dict_v_col_t*>(col);
  		}
  
  		col_no = dict_col_get_no(col);
  
  		/* Process the Doc ID column */
  		if (*doc_id > 0
  		    && col_no == index->table->fts->doc_col
  		    && !col->is_virtual()) {
  			fts_write_doc_id((byte*) &write_doc_id, *doc_id);
  
  			/* Note: field->data now points to a value on the
  			stack: &write_doc_id after dfield_set_data(). Because
  			there is only one doc_id per row, it shouldn't matter.
  			We allocate a new buffer before we leave the function
  			later below. */
  
  			dfield_set_data(
  				field, &write_doc_id, sizeof(write_doc_id));
  
  			field->type.mtype = ifield->col->mtype;
  			field->type.prtype = ifield->col->prtype;
  			field->type.mbminlen = 0;
  			field->type.mbmaxlen = 0;
  			field->type.len = ifield->col->len;
  		} else {
  			/* Use callback to get the virtual column value */
  			if (col->is_virtual()) {
  				dict_index_t*	clust_index
  					= dict_table_get_first_index(new_table);
  
                                  if (!vcol_storage &&
                                      innobase_allocate_row_for_vcol(trx->mysql_thd, clust_index, v_heap, &my_table, &record, &vcol_storage)) {
  					*err = DB_OUT_OF_MEMORY;
  					goto error;
  				}
  
  				row_field = innobase_get_computed_value(
  					row, v_col, clust_index,
  					v_heap, NULL, ifield, trx->mysql_thd,
  					my_table, record, old_table, NULL,
  					NULL);
  
  				if (row_field == NULL) {
  					*err = DB_COMPUTE_VALUE_FAILED;
  					goto error;
  				}
  				dfield_copy(field, row_field);
  			} else {
  				row_field = dtuple_get_nth_field(row, col_no);
  				dfield_copy(field, row_field);
  			}
  
  
  			/* Tokenize and process data for FTS */
  			if (index->type & DICT_FTS) {
  				fts_doc_item_t*	doc_item;
  				byte*		value;
  				void*		ptr;
  				const ulint	max_trial_count = 10000;
  				ulint		trial_count = 0;
  
  				/* fetch Doc ID if it already exists
  				in the row, and not supplied by the
  				caller. Even if the value column is
  				NULL, we still need to get the Doc
  				ID so to maintain the correct max
  				Doc ID */
  				if (*doc_id == 0) {
  					const dfield_t*	doc_field;
  					doc_field = dtuple_get_nth_field(
  						row,
  						index->table->fts->doc_col);
  					*doc_id = (doc_id_t) mach_read_from_8(
  						static_cast<byte*>(
  						dfield_get_data(doc_field)));
  
  					if (*doc_id == 0) {
  						ib::warn() << "FTS Doc ID is"
  							" zero. Record"
  							" skipped";
  						goto error;
  					}
  				}
  
  				if (dfield_is_null(field)) {
  					n_row_added = 1;
  					continue;
  				}
  
  				ptr = ut_malloc_nokey(sizeof(*doc_item)
  						      + field->len);
  
  				doc_item = static_cast<fts_doc_item_t*>(ptr);
  				value = static_cast<byte*>(ptr)
  					+ sizeof(*doc_item);
  				memcpy(value, field->data, field->len);
  				field->data = value;
  
  				doc_item->field = field;
  				doc_item->doc_id = *doc_id;
  
  				bucket = *doc_id % fts_sort_pll_degree;
  
  				/* Add doc item to fts_doc_list */
  				mutex_enter(&psort_info[bucket].mutex);
  
  				if (psort_info[bucket].error == DB_SUCCESS) {
  					UT_LIST_ADD_LAST(
  						psort_info[bucket].fts_doc_list,
  						doc_item);
  					psort_info[bucket].memory_used +=
  						sizeof(*doc_item) + field->len;
  				} else {
  					ut_free(doc_item);
  				}
  
  				mutex_exit(&psort_info[bucket].mutex);
  
  				/* Sleep when memory used exceeds limit*/
  				while (psort_info[bucket].memory_used
  				       > FTS_PENDING_DOC_MEMORY_LIMIT
  				       && trial_count++ < max_trial_count) {
  					os_thread_sleep(1000);
  				}
  
  				n_row_added = 1;
  				continue;
  			}
  
  			if (field->len != UNIV_SQL_NULL
  			    && col->mtype == DATA_MYSQL
  			    && col->len != field->len) {
  				if (conv_heap != NULL) {
  					row_merge_buf_redundant_convert(
  						row_field, field, col->len,
  						dict_table_page_size(old_table),
  						conv_heap);
  				} else {
  					/* Field length mismatch should not
  					happen when rebuilding redundant row
  					format table. */
  					ut_ad(dict_table_is_comp(index->table));
  				}
  			}
  		}
  
  		len = dfield_get_len(field);
  
  		if (dfield_is_null(field)) {
  			ut_ad(!(col->prtype & DATA_NOT_NULL));
  			continue;
  		} else if (!ext) {
  		} else if (dict_index_is_clust(index)) {
  			/* Flag externally stored fields. */
  			const byte*	buf = row_ext_lookup(ext, col_no,
  							     &len);
  			if (UNIV_LIKELY_NULL(buf)) {
  				ut_a(buf != field_ref_zero);
  				if (i < dict_index_get_n_unique(index)) {
  					dfield_set_data(field, buf, len);
  				} else {
  					dfield_set_ext(field);
  					len = dfield_get_len(field);
  				}
  			}
  		} else if (!col->is_virtual()) {
  			/* Only non-virtual column are stored externally */
  			const byte*	buf = row_ext_lookup(ext, col_no,
  							     &len);
  			if (UNIV_LIKELY_NULL(buf)) {
  				ut_a(buf != field_ref_zero);
  				dfield_set_data(field, buf, len);
  			}
  		}
  
  		/* If a column prefix index, take only the prefix */
  
  		if (ifield->prefix_len) {
  			len = dtype_get_at_most_n_mbchars(
  				col->prtype,
  				col->mbminlen, col->mbmaxlen,
  				ifield->prefix_len,
  				len,
  				static_cast<char*>(dfield_get_data(field)));
  			dfield_set_len(field, len);
  		}
  
  		ut_ad(len <= col->len
  		      || DATA_LARGE_MTYPE(col->mtype));
  
  		fixed_len = ifield->fixed_len;
  		if (fixed_len && !dict_table_is_comp(index->table)
  		    && col->mbminlen != col->mbmaxlen) {
  			/* CHAR in ROW_FORMAT=REDUNDANT is always
  			fixed-length, but in the temporary file it is
  			variable-length for variable-length character
  			sets. */
  			fixed_len = 0;
  		}
  
  		if (fixed_len) {
  #ifdef UNIV_DEBUG
  			/* len should be between size calcualted base on
  			mbmaxlen and mbminlen */
  			ut_ad(len <= fixed_len);
  			ut_ad(!col->mbmaxlen || len >= col->mbminlen
  			      * (fixed_len / col->mbmaxlen));
  
  			ut_ad(!dfield_is_ext(field));
  #endif /* UNIV_DEBUG */
  		} else if (dfield_is_ext(field)) {
  			extra_size += 2;
  		} else if (len < 128
  			   || (!DATA_BIG_COL(col))) {
  			extra_size++;
  		} else {
  			/* For variable-length columns, we look up the
  			maximum length from the column itself.  If this
  			is a prefix index column shorter than 256 bytes,
  			this will waste one byte. */
  			extra_size += 2;
  		}
  		data_size += len;
  	}
  
  	/* If this is FTS index, we already populated the sort buffer, return
  	here */
  	if (index->type & DICT_FTS) {
  		goto end;
  	}
  
  #ifdef UNIV_DEBUG
  	{
  		ulint	size;
  		ulint	extra;
  
  		size = rec_get_converted_size_temp(
  			index, entry->fields, n_fields, &extra);
  
  		ut_ad(data_size + extra_size == size);
  		ut_ad(extra_size == extra);
  	}
  #endif /* UNIV_DEBUG */
  
  	/* Add to the total size of the record in row_merge_block_t
  	the encoded length of extra_size and the extra bytes (extra_size).
  	See row_merge_buf_write() for the variable-length encoding
  	of extra_size. */
  	data_size += (extra_size + 1) + ((extra_size + 1) >= 0x80);
  
  	/* Record size can exceed page size while converting to
  	redundant row format. But there is assert
  	ut_ad(size < srv_page_size) in rec_offs_data_size().
  	It may hit the assert before attempting to insert the row. */
  	if (conv_heap != NULL && data_size > srv_page_size) {
  		*err = DB_TOO_BIG_RECORD;
  	}
  
  	ut_ad(data_size < srv_sort_buf_size);
  
  	/* Reserve bytes for the end marker of row_merge_block_t. */
  	if (buf->total_size + data_size >= srv_sort_buf_size) {
  		goto error;
  	}
  
  	buf->total_size += data_size;
  	buf->n_tuples++;
  	n_row_added++;
  
  	field = entry->fields;
  
  	/* Copy the data fields. */
  
  	do {
  		dfield_dup(field++, buf->heap);
  	} while (--n_fields);
  
  	if (conv_heap != NULL) {
  		mem_heap_empty(conv_heap);
  	}
  
  end:
          if (vcol_storage)
  		innobase_free_row_for_vcol(vcol_storage);
  	DBUG_RETURN(n_row_added);
  
  error:
          if (vcol_storage)
  		innobase_free_row_for_vcol(vcol_storage);
          DBUG_RETURN(0);
  }
  
  /*************************************************************//**
  Report a duplicate key. */
  void
  row_merge_dup_report(
  /*=================*/
  	row_merge_dup_t*	dup,	/*!< in/out: for reporting duplicates */
  	const dfield_t*		entry)	/*!< in: duplicate index entry */
  {
  	if (!dup->n_dup++) {
  		/* Only report the first duplicate record,
  		but count all duplicate records. */
  		innobase_fields_to_mysql(dup->table, dup->index, entry);
  	}
  }
  
  /*************************************************************//**
  Compare two tuples.
  @return positive, 0, negative if a is greater, equal, less, than b,
  respectively */
  static MY_ATTRIBUTE((warn_unused_result))
  int
  row_merge_tuple_cmp(
  /*================*/
  	ulint			n_uniq,	/*!< in: number of unique fields */
  	ulint			n_field,/*!< in: number of fields */
  	const mtuple_t&		a,	/*!< in: first tuple to be compared */
  	const mtuple_t&		b,	/*!< in: second tuple to be compared */
  	row_merge_dup_t*	dup)	/*!< in/out: for reporting duplicates,
  					NULL if non-unique index */
  {
  	int		cmp;
  	const dfield_t*	af	= a.fields;
  	const dfield_t*	bf	= b.fields;
  	ulint		n	= n_uniq;
  
  	ut_ad(n_uniq > 0);
  	ut_ad(n_uniq <= n_field);
  
  	/* Compare the fields of the tuples until a difference is
  	found or we run out of fields to compare.  If !cmp at the
  	end, the tuples are equal. */
  	do {
  		cmp = cmp_dfield_dfield(af++, bf++);
  	} while (!cmp && --n);
  
  	if (cmp) {
  		return(cmp);
  	}
  
  	if (dup) {
  		/* Report a duplicate value error if the tuples are
  		logically equal.  NULL columns are logically inequal,
  		although they are equal in the sorting order.  Find
  		out if any of the fields are NULL. */
  		for (const dfield_t* df = a.fields; df != af; df++) {
  			if (dfield_is_null(df)) {
  				goto no_report;
  			}
  		}
  
  		row_merge_dup_report(dup, a.fields);
  	}
  
  no_report:
  	/* The n_uniq fields were equal, but we compare all fields so
  	that we will get the same (internal) order as in the B-tree. */
  	for (n = n_field - n_uniq + 1; --n; ) {
  		cmp = cmp_dfield_dfield(af++, bf++);
  		if (cmp) {
  			return(cmp);
  		}
  	}
  
  	/* This should never be reached, except in a secondary index
  	when creating a secondary index and a PRIMARY KEY, and there
  	is a duplicate in the PRIMARY KEY that has not been detected
  	yet. Internally, an index must never contain duplicates. */
  	return(cmp);
  }
  
  /** Wrapper for row_merge_tuple_sort() to inject some more context to
  UT_SORT_FUNCTION_BODY().
  @param tuples array of tuples that being sorted
  @param aux work area, same size as tuples[]
  @param low lower bound of the sorting area, inclusive
  @param high upper bound of the sorting area, inclusive */
  #define row_merge_tuple_sort_ctx(tuples, aux, low, high)		\
  	row_merge_tuple_sort(n_uniq, n_field, dup, tuples, aux, low, high)
  /** Wrapper for row_merge_tuple_cmp() to inject some more context to
  UT_SORT_FUNCTION_BODY().
  @param a first tuple to be compared
  @param b second tuple to be compared
  @return positive, 0, negative, if a is greater, equal, less, than b,
  respectively */
  #define row_merge_tuple_cmp_ctx(a,b)			\
  	row_merge_tuple_cmp(n_uniq, n_field, a, b, dup)
  
  /**********************************************************************//**
  Merge sort the tuple buffer in main memory. */
  static
  void
  row_merge_tuple_sort(
  /*=================*/
  	ulint			n_uniq,	/*!< in: number of unique fields */
  	ulint			n_field,/*!< in: number of fields */
  	row_merge_dup_t*	dup,	/*!< in/out: reporter of duplicates
  					(NULL if non-unique index) */
  	mtuple_t*		tuples,	/*!< in/out: tuples */
  	mtuple_t*		aux,	/*!< in/out: work area */
  	ulint			low,	/*!< in: lower bound of the
  					sorting area, inclusive */
  	ulint			high)	/*!< in: upper bound of the
  					sorting area, exclusive */
  {
  	ut_ad(n_field > 0);
  	ut_ad(n_uniq <= n_field);
  
  	UT_SORT_FUNCTION_BODY(row_merge_tuple_sort_ctx,
  			      tuples, aux, low, high, row_merge_tuple_cmp_ctx);
  }
  
  /******************************************************//**
  Sort a buffer. */
  void
  row_merge_buf_sort(
  /*===============*/
  	row_merge_buf_t*	buf,	/*!< in/out: sort buffer */
  	row_merge_dup_t*	dup)	/*!< in/out: reporter of duplicates
  					(NULL if non-unique index) */
  {
  	ut_ad(!dict_index_is_spatial(buf->index));
  
  	row_merge_tuple_sort(dict_index_get_n_unique(buf->index),
  			     dict_index_get_n_fields(buf->index),
  			     dup,
  			     buf->tuples, buf->tmp_tuples, 0, buf->n_tuples);
  }
  
  /******************************************************//**
  Write a buffer to a block. */
  void
  row_merge_buf_write(
  /*================*/
  	const row_merge_buf_t*	buf,	/*!< in: sorted buffer */
  	const merge_file_t*	of UNIV_UNUSED,
  					/*!< in: output file */
  	row_merge_block_t*	block)	/*!< out: buffer for writing to file */
  {
  	const dict_index_t*	index	= buf->index;
  	ulint			n_fields= dict_index_get_n_fields(index);
  	byte*			b	= &block[0];
  
  	DBUG_ENTER("row_merge_buf_write");
  
  	for (ulint i = 0; i < buf->n_tuples; i++) {
  		const mtuple_t*	entry	= &buf->tuples[i];
  
  		row_merge_buf_encode(&b, index, entry, n_fields);
  		ut_ad(b < &block[srv_sort_buf_size]);
  
  		DBUG_LOG("ib_merge_sort",
  			 reinterpret_cast<const void*>(b) << ','
  			 << of->fd << ',' << of->offset << ' ' <<
  			 i << ": " <<
  			 rec_printer(entry->fields, n_fields).str());
  	}
  
  	/* Write an "end-of-chunk" marker. */
  	ut_a(b < &block[srv_sort_buf_size]);
  	ut_a(b == &block[0] + buf->total_size);
  	*b++ = 0;
  #ifdef UNIV_DEBUG_VALGRIND
  	/* The rest of the block is uninitialized.  Initialize it
  	to avoid bogus warnings. */
  	memset(b, 0xff, &block[srv_sort_buf_size] - b);
  #endif /* UNIV_DEBUG_VALGRIND */
  	DBUG_LOG("ib_merge_sort",
  		 "write " << reinterpret_cast<const void*>(b) << ','
  		 << of->fd << ',' << of->offset << " EOF");
  	DBUG_VOID_RETURN;
  }
  
  /******************************************************//**
  Create a memory heap and allocate space for row_merge_rec_offsets()
  and mrec_buf_t[3].
  @return memory heap */
  static
  mem_heap_t*
  row_merge_heap_create(
  /*==================*/
  	const dict_index_t*	index,		/*!< in: record descriptor */
  	mrec_buf_t**		buf,		/*!< out: 3 buffers */
  	ulint**			offsets1,	/*!< out: offsets */
  	ulint**			offsets2)	/*!< out: offsets */
  {
  	ulint		i	= 1 + REC_OFFS_HEADER_SIZE
  		+ dict_index_get_n_fields(index);
  	mem_heap_t*	heap	= mem_heap_create(2 * i * sizeof **offsets1
  						  + 3 * sizeof **buf);
  
  	*buf = static_cast<mrec_buf_t*>(
  		mem_heap_alloc(heap, 3 * sizeof **buf));
  	*offsets1 = static_cast<ulint*>(
  		mem_heap_alloc(heap, i * sizeof **offsets1));
  	*offsets2 = static_cast<ulint*>(
  		mem_heap_alloc(heap, i * sizeof **offsets2));
  
  	(*offsets1)[0] = (*offsets2)[0] = i;
  	(*offsets1)[1] = (*offsets2)[1] = dict_index_get_n_fields(index);
  
  	return(heap);
  }
  
  /** Read a merge block from the file system.
  @return whether the request was completed successfully */
  bool
  row_merge_read(
  /*===========*/
  	const pfs_os_file_t&	fd,	/*!< in: file descriptor */
  	ulint			offset,	/*!< in: offset where to read
  					in number of row_merge_block_t
  					elements */
  	row_merge_block_t*	buf,	/*!< out: data */
  	row_merge_block_t*	crypt_buf, /*!< in: crypt buf or NULL */
  	ulint			space)		/*!< in: space id */
  {
  	os_offset_t	ofs = ((os_offset_t) offset) * srv_sort_buf_size;
  
  	DBUG_ENTER("row_merge_read");
  	DBUG_LOG("ib_merge_sort", "fd=" << fd << " ofs=" << ofs);
  	DBUG_EXECUTE_IF("row_merge_read_failure", DBUG_RETURN(FALSE););
  
  	IORequest	request(IORequest::READ);
  	const bool	success = os_file_read_no_error_handling(
  		request, fd, buf, ofs, srv_sort_buf_size, 0);
  
  	/* If encryption is enabled decrypt buffer */
  	if (success && log_tmp_is_encrypted()) {
  		if (!log_tmp_block_decrypt(buf, srv_sort_buf_size,
  					   crypt_buf, ofs, space)) {
  			return (FALSE);
  		}
  
  		srv_stats.n_merge_blocks_decrypted.inc();
  		memcpy(buf, crypt_buf, srv_sort_buf_size);
  	}
  
  #ifdef POSIX_FADV_DONTNEED
  	/* Each block is read exactly once.  Free up the file cache. */
  	posix_fadvise(fd, ofs, srv_sort_buf_size, POSIX_FADV_DONTNEED);
  #endif /* POSIX_FADV_DONTNEED */
  
  	if (!success) {
  		ib::error() << "Failed to read merge block at " << ofs;
  	}
  
  	DBUG_RETURN(success);
  }
  
  /********************************************************************//**
  Write a merge block to the file system.
  @return whether the request was completed successfully */
  UNIV_INTERN
  bool
  row_merge_write(
  /*============*/
  	const pfs_os_file_t&	fd,			/*!< in: file descriptor */
  	ulint		offset,			/*!< in: offset where to write,
  						in number of row_merge_block_t elements */
  	const void*	buf,			/*!< in: data */
  	void*		crypt_buf,		/*!< in: crypt buf or NULL */
  	ulint		space)			/*!< in: space id */
  {
  	size_t		buf_len = srv_sort_buf_size;
  	os_offset_t	ofs = buf_len * (os_offset_t) offset;
  	void*		out_buf = (void *)buf;
  
  	DBUG_ENTER("row_merge_write");
  	DBUG_LOG("ib_merge_sort", "fd=" << fd << " ofs=" << ofs);
  	DBUG_EXECUTE_IF("row_merge_write_failure", DBUG_RETURN(FALSE););
  
  	/* For encrypted tables, encrypt data before writing */
  	if (log_tmp_is_encrypted()) {
  		if (!log_tmp_block_encrypt(static_cast<const byte*>(buf),
  					   buf_len,
  					   static_cast<byte*>(crypt_buf),
  					   ofs, space)) {
  			return false;
  		}
  
  		srv_stats.n_merge_blocks_encrypted.inc();
  		out_buf = crypt_buf;
  	}
  
  	IORequest	request(IORequest::WRITE);
  	const bool	success = os_file_write(
  		request, "(merge)", fd, out_buf, ofs, buf_len);
  
  #ifdef POSIX_FADV_DONTNEED
  	/* The block will be needed on the next merge pass,
  	but it can be evicted from the file cache meanwhile. */
  	posix_fadvise(fd, ofs, buf_len, POSIX_FADV_DONTNEED);
  #endif /* POSIX_FADV_DONTNEED */
  
  	DBUG_RETURN(success);
  }
  
  /********************************************************************//**
  Read a merge record.
  @return pointer to next record, or NULL on I/O error or end of list */
  const byte*
  row_merge_read_rec(
  /*===============*/
  	row_merge_block_t*	block,	/*!< in/out: file buffer */
  	mrec_buf_t*		buf,	/*!< in/out: secondary buffer */
  	const byte*		b,	/*!< in: pointer to record */
  	const dict_index_t*	index,	/*!< in: index of the record */
  	const pfs_os_file_t&	fd,	/*!< in: file descriptor */
  	ulint*			foffs,	/*!< in/out: file offset */
  	const mrec_t**		mrec,	/*!< out: pointer to merge record,
  					or NULL on end of list
  					(non-NULL on I/O error) */
  	ulint*			offsets,/*!< out: offsets of mrec */
  	row_merge_block_t*	crypt_block, /*!< in: crypt buf or NULL */
  	ulint			space) /*!< in: space id */
  {
  	ulint	extra_size;
  	ulint	data_size;
  	ulint	avail_size;
  
  	ut_ad(b >= &block[0]);
  	ut_ad(b < &block[srv_sort_buf_size]);
  
  	ut_ad(*offsets == 1 + REC_OFFS_HEADER_SIZE
  	      + dict_index_get_n_fields(index));
  
  	DBUG_ENTER("row_merge_read_rec");
  
  	extra_size = *b++;
  
  	if (UNIV_UNLIKELY(!extra_size)) {
  		/* End of list */
  		*mrec = NULL;
  		DBUG_LOG("ib_merge_sort",
  			 "read " << reinterpret_cast<const void*>(b) << ',' <<
  			 reinterpret_cast<const void*>(block) << ',' <<
  			 fd << ',' << *foffs << " EOF");
  		DBUG_RETURN(NULL);
  	}
  
  	if (extra_size >= 0x80) {
  		/* Read another byte of extra_size. */
  
  		if (UNIV_UNLIKELY(b >= &block[srv_sort_buf_size])) {
  			if (!row_merge_read(fd, ++(*foffs), block,
  					    crypt_block,
  					    space)) {
  err_exit:
  				/* Signal I/O error. */
  				*mrec = b;
  				DBUG_RETURN(NULL);
  			}
  
  			/* Wrap around to the beginning of the buffer. */
  			b = &block[0];
  		}
  
  		extra_size = (extra_size & 0x7f) << 8;
  		extra_size |= *b++;
  	}
  
  	/* Normalize extra_size.  Above, value 0 signals "end of list". */
  	extra_size--;
  
  	/* Read the extra bytes. */
  
  	if (UNIV_UNLIKELY(b + extra_size >= &block[srv_sort_buf_size])) {
  		/* The record spans two blocks.  Copy the entire record
  		to the auxiliary buffer and handle this as a special
  		case. */
  
  		avail_size = ulint(&block[srv_sort_buf_size] - b);
  		ut_ad(avail_size < sizeof *buf);
  		memcpy(*buf, b, avail_size);
  
  		if (!row_merge_read(fd, ++(*foffs), block,
  				    crypt_block,
  				    space)) {
  
  			goto err_exit;
  		}
  
  		/* Wrap around to the beginning of the buffer. */
  		b = &block[0];
  
  		/* Copy the record. */
  		memcpy(*buf + avail_size, b, extra_size - avail_size);
  		b += extra_size - avail_size;
  
  		*mrec = *buf + extra_size;
  
  		rec_init_offsets_temp(*mrec, index, offsets);
  
  		data_size = rec_offs_data_size(offsets);
  
  		/* These overflows should be impossible given that
  		records are much smaller than either buffer, and
  		the record starts near the beginning of each buffer. */
  		ut_a(extra_size + data_size < sizeof *buf);
  		ut_a(b + data_size < &block[srv_sort_buf_size]);
  
  		/* Copy the data bytes. */
  		memcpy(*buf + extra_size, b, data_size);
  		b += data_size;
  
  		goto func_exit;
  	}
  
  	*mrec = b + extra_size;
  
  	rec_init_offsets_temp(*mrec, index, offsets);
  
  	data_size = rec_offs_data_size(offsets);
  	ut_ad(extra_size + data_size < sizeof *buf);
  
  	b += extra_size + data_size;
  
  	if (UNIV_LIKELY(b < &block[srv_sort_buf_size])) {
  		/* The record fits entirely in the block.
  		This is the normal case. */
  		goto func_exit;
  	}
  
  	/* The record spans two blocks.  Copy it to buf. */
  
  	b -= extra_size + data_size;
  	avail_size = ulint(&block[srv_sort_buf_size] - b);
  	memcpy(*buf, b, avail_size);
  	*mrec = *buf + extra_size;
  
  	/* We cannot invoke rec_offs_make_valid() here, because there
  	are no REC_N_NEW_EXTRA_BYTES between extra_size and data_size.
  	Similarly, rec_offs_validate() would fail, because it invokes
  	rec_get_status(). */
  	ut_d(offsets[2] = (ulint) *mrec);
  	ut_d(offsets[3] = (ulint) index);
  
  	if (!row_merge_read(fd, ++(*foffs), block,
  			    crypt_block,
  			    space)) {
  
  		goto err_exit;
  	}
  
  	/* Wrap around to the beginning of the buffer. */
  	b = &block[0];
  
  	/* Copy the rest of the record. */
  	memcpy(*buf + avail_size, b, extra_size + data_size - avail_size);
  	b += extra_size + data_size - avail_size;
  
  func_exit:
  	DBUG_LOG("ib_merge_sort",
  		 reinterpret_cast<const void*>(b) << ',' <<
  		 reinterpret_cast<const void*>(block)
  		 << ",fd=" << fd << ',' << *foffs << ": "
  		 << rec_printer(*mrec, 0, offsets).str());
  	DBUG_RETURN(b);
  }
  
  /********************************************************************//**
  Write a merge record. */
  static
  void
  row_merge_write_rec_low(
  /*====================*/
  	byte*		b,	/*!< out: buffer */
  	ulint		e,	/*!< in: encoded extra_size */
  #ifndef DBUG_OFF
  	ulint		size,	/*!< in: total size to write */
  	const pfs_os_file_t&	fd,	/*!< in: file descriptor */
  	ulint		foffs,	/*!< in: file offset */
  #endif /* !DBUG_OFF */
  	const mrec_t*	mrec,	/*!< in: record to write */
  	const ulint*	offsets)/*!< in: offsets of mrec */
  #ifdef DBUG_OFF
  # define row_merge_write_rec_low(b, e, size, fd, foffs, mrec, offsets)	\
  	row_merge_write_rec_low(b, e, mrec, offsets)
  #endif /* DBUG_OFF */
  {
  	DBUG_ENTER("row_merge_write_rec_low");
  
  #ifndef DBUG_OFF
  	const byte* const end = b + size;
  #endif /* DBUG_OFF */
  	DBUG_ASSERT(e == rec_offs_extra_size(offsets) + 1);
  
  	DBUG_LOG("ib_merge_sort",
  		 reinterpret_cast<const void*>(b) << ",fd=" << fd << ','
  		 << foffs << ": " << rec_printer(mrec, 0, offsets).str());
  
  	if (e < 0x80) {
  		*b++ = (byte) e;
  	} else {
  		*b++ = (byte) (0x80 | (e >> 8));
  		*b++ = (byte) e;
  	}
  
  	memcpy(b, mrec - rec_offs_extra_size(offsets), rec_offs_size(offsets));
  	DBUG_SLOW_ASSERT(b + rec_offs_size(offsets) == end);
  	DBUG_VOID_RETURN;
  }
  
  /********************************************************************//**
  Write a merge record.
  @return pointer to end of block, or NULL on error */
  static
  byte*
  row_merge_write_rec(
  /*================*/
  	row_merge_block_t*	block,	/*!< in/out: file buffer */
  	mrec_buf_t*		buf,	/*!< in/out: secondary buffer */
  	byte*			b,	/*!< in: pointer to end of block */
  	const pfs_os_file_t&	fd,	/*!< in: file descriptor */
  	ulint*			foffs,	/*!< in/out: file offset */
  	const mrec_t*		mrec,	/*!< in: record to write */
  	const ulint*            offsets,/*!< in: offsets of mrec */
  	row_merge_block_t*	crypt_block, /*!< in: crypt buf or NULL */
  	ulint			space)	   /*!< in: space id */
  {
  	ulint	extra_size;
  	ulint	size;
  	ulint	avail_size;
  
  	ut_ad(block);
  	ut_ad(buf);
  	ut_ad(b >= &block[0]);
  	ut_ad(b < &block[srv_sort_buf_size]);
  	ut_ad(mrec);
  	ut_ad(foffs);
  	ut_ad(mrec < &block[0] || mrec > &block[srv_sort_buf_size]);
  	ut_ad(mrec < buf[0] || mrec > buf[1]);
  
  	/* Normalize extra_size.  Value 0 signals "end of list". */
  	extra_size = rec_offs_extra_size(offsets) + 1;
  
  	size = extra_size + (extra_size >= 0x80)
  		+ rec_offs_data_size(offsets);
  
  	if (UNIV_UNLIKELY(b + size >= &block[srv_sort_buf_size])) {
  		/* The record spans two blocks.
  		Copy it to the temporary buffer first. */
  		avail_size = ulint(&block[srv_sort_buf_size] - b);
  
  		row_merge_write_rec_low(buf[0],
  					extra_size, size, fd, *foffs,
  					mrec, offsets);
  
  		/* Copy the head of the temporary buffer, write
  		the completed block, and copy the tail of the
  		record to the head of the new block. */
  		memcpy(b, buf[0], avail_size);
  
  		if (!row_merge_write(fd, (*foffs)++, block,
  				     crypt_block,
  				     space)) {
  			return(NULL);
  		}
  
  		UNIV_MEM_INVALID(&block[0], srv_sort_buf_size);
  
  		/* Copy the rest. */
  		b = &block[0];
  		memcpy(b, buf[0] + avail_size, size - avail_size);
  		b += size - avail_size;
  	} else {
  		row_merge_write_rec_low(b, extra_size, size, fd, *foffs,
  					mrec, offsets);
  		b += size;
  	}
  
  	return(b);
  }
  
  /********************************************************************//**
  Write an end-of-list marker.
  @return pointer to end of block, or NULL on error */
  static
  byte*
  row_merge_write_eof(
  /*================*/
  	row_merge_block_t*	block,		/*!< in/out: file buffer */
  	byte*			b,		/*!< in: pointer to end of block */
  	const pfs_os_file_t&	fd,		/*!< in: file descriptor */
  	ulint*			foffs,		/*!< in/out: file offset */
  	row_merge_block_t*	crypt_block, 	/*!< in: crypt buf or NULL */
  	ulint			space)	   	/*!< in: space id */
  {
  	ut_ad(block);
  	ut_ad(b >= &block[0]);
  	ut_ad(b < &block[srv_sort_buf_size]);
  	ut_ad(foffs);
  
  	DBUG_ENTER("row_merge_write_eof");
  	DBUG_LOG("ib_merge_sort",
  		 reinterpret_cast<const void*>(b) << ',' <<
  		 reinterpret_cast<const void*>(block) <<
  		 ",fd=" << fd << ',' << *foffs);
  
  	*b++ = 0;
  	UNIV_MEM_ASSERT_RW(&block[0], b - &block[0]);
  	UNIV_MEM_ASSERT_W(&block[0], srv_sort_buf_size);
  
  #ifdef UNIV_DEBUG_VALGRIND
  	/* The rest of the block is uninitialized.  Initialize it
  	to avoid bogus warnings. */
  	memset(b, 0xff, ulint(&block[srv_sort_buf_size] - b));
  #endif /* UNIV_DEBUG_VALGRIND */
  
  	if (!row_merge_write(fd, (*foffs)++, block, crypt_block, space)) {
  		DBUG_RETURN(NULL);
  	}
  
  	UNIV_MEM_INVALID(&block[0], srv_sort_buf_size);
  	DBUG_RETURN(&block[0]);
  }
  
  /** Create a temporary file if it has not been created already.
  @param[in,out]	tmpfd	temporary file handle
  @param[in]	path	location for creating temporary file
  @return true on success, false on error */
  static MY_ATTRIBUTE((warn_unused_result))
  bool
  row_merge_tmpfile_if_needed(
  	pfs_os_file_t*		tmpfd,
  	const char*	path)
  {
  	if (*tmpfd == OS_FILE_CLOSED) {
  		*tmpfd = row_merge_file_create_low(path);
  		if (*tmpfd != OS_FILE_CLOSED) {
  			MONITOR_ATOMIC_INC(MONITOR_ALTER_TABLE_SORT_FILES);
  		}
  	}
  
  	return(*tmpfd != OS_FILE_CLOSED);
  }
  
  /** Create a temporary file for merge sort if it was not created already.
  @param[in,out]	file	merge file structure
  @param[in]	nrec	number of records in the file
  @param[in]	path	location for creating temporary file
  @return  true on success, false on error */
  static MY_ATTRIBUTE((warn_unused_result))
  bool
  row_merge_file_create_if_needed(
  	merge_file_t*	file,
  	pfs_os_file_t*	tmpfd,
  	ulint		nrec,
  	const char*	path)
  {
  	ut_ad(file->fd == OS_FILE_CLOSED || *tmpfd != OS_FILE_CLOSED);
  	if (file->fd == OS_FILE_CLOSED && row_merge_file_create(file, path)!= OS_FILE_CLOSED) {
  		MONITOR_ATOMIC_INC(MONITOR_ALTER_TABLE_SORT_FILES);
  		if (!row_merge_tmpfile_if_needed(tmpfd, path) ) {
  			return(false);
  		}
  
  		file->n_rec = nrec;
  	}
  
  	ut_ad(file->fd == OS_FILE_CLOSED || *tmpfd != OS_FILE_CLOSED);
  	return(file->fd != OS_FILE_CLOSED);
  }
  
  /** Copy the merge data tuple from another merge data tuple.
  @param[in]	mtuple		source merge data tuple
  @param[in,out]	prev_mtuple	destination merge data tuple
  @param[in]	n_unique	number of unique fields exist in the mtuple
  @param[in,out]	heap		memory heap where last_mtuple allocated */
  static
  void
  row_mtuple_create(
  	const mtuple_t*	mtuple,
  	mtuple_t*	prev_mtuple,
  	ulint		n_unique,
  	mem_heap_t*	heap)
  {
  	memcpy(prev_mtuple->fields, mtuple->fields,
  	       n_unique * sizeof *mtuple->fields);
  
  	dfield_t*	field = prev_mtuple->fields;
  
  	for (ulint i = 0; i < n_unique; i++) {
  		dfield_dup(field++, heap);
  	}
  }
  
  /** Compare two merge data tuples.
  @param[in]	prev_mtuple	merge data tuple
  @param[in]	current_mtuple	merge data tuple
  @param[in,out]	dup		reporter of duplicates
  @retval positive, 0, negative if current_mtuple is greater, equal, less, than
  last_mtuple. */
  static
  int
  row_mtuple_cmp(
  	const mtuple_t*		prev_mtuple,
  	const mtuple_t*		current_mtuple,
  	row_merge_dup_t*	dup)
  {
  	ut_ad(dict_index_is_clust(dup->index));
  	const ulint	n_unique = dict_index_get_n_unique(dup->index);
  
  	return(row_merge_tuple_cmp(
  		       n_unique, n_unique, *current_mtuple, *prev_mtuple, dup));
  }
  
  /** Insert cached spatial index rows.
  @param[in]	trx_id		transaction id
  @param[in]	sp_tuples	cached spatial rows
  @param[in]	num_spatial	number of spatial indexes
  @param[in,out]	row_heap	heap for insert
  @param[in,out]	sp_heap		heap for tuples
  @param[in,out]	pcur		cluster index cursor
  @param[in,out]	mtr		mini transaction
  @param[in,out]	mtr_committed	whether scan_mtr got committed
  @return DB_SUCCESS or error number */
  static
  dberr_t
  row_merge_spatial_rows(
  	trx_id_t		trx_id,
  	index_tuple_info_t**	sp_tuples,
  	ulint			num_spatial,
  	mem_heap_t*		row_heap,
  	mem_heap_t*		sp_heap,
  	btr_pcur_t*		pcur,
  	mtr_t*			mtr,
  	bool*			mtr_committed)
  {
  	dberr_t			err = DB_SUCCESS;
  
  	if (sp_tuples == NULL) {
  		return(DB_SUCCESS);
  	}
  
  	ut_ad(sp_heap != NULL);
  
  	for (ulint j = 0; j < num_spatial; j++) {
  		err = sp_tuples[j]->insert(
  			trx_id, row_heap,
  			pcur, mtr, mtr_committed);
  
  		if (err != DB_SUCCESS) {
  			return(err);
  		}
  	}
  
  	mem_heap_empty(sp_heap);
  
  	return(err);
  }
  
  /** Check if the geometry field is valid.
  @param[in]	row		the row
  @param[in]	index		spatial index
  @return true if it's valid, false if it's invalid. */
  static
  bool
  row_geo_field_is_valid(
  	const dtuple_t*		row,
  	dict_index_t*		index)
  {
  	const dict_field_t*	ind_field
  		= dict_index_get_nth_field(index, 0);
  	const dict_col_t*	col
  		= ind_field->col;
  	ulint			col_no
  		= dict_col_get_no(col);
  	const dfield_t*		dfield
  		= dtuple_get_nth_field(row, col_no);
  
  	if (dfield_is_null(dfield)
  	    || dfield_get_len(dfield) < GEO_DATA_HEADER_SIZE) {
  		return(false);
  	}
  
  	return(true);
  }
  
  /** Reads clustered index of the table and create temporary files
  containing the index entries for the indexes to be built.
  @param[in]	trx		transaction
  @param[in,out]	table		MySQL table object, for reporting erroneous
  				records
  @param[in]	old_table	table where rows are read from
  @param[in]	new_table	table where indexes are created; identical to
  				old_table unless creating a PRIMARY KEY
  @param[in]	online		true if creating indexes online
  @param[in]	index		indexes to be created
  @param[in]	fts_sort_idx	full-text index to be created, or NULL
  @param[in]	psort_info	parallel sort info for fts_sort_idx creation,
  				or NULL
  @param[in]	files		temporary files
  @param[in]	key_numbers	MySQL key numbers to create
  @param[in]	n_index		number of indexes to create
  @param[in]	defaults	default values of added, changed columns, or NULL
  @param[in]	add_v		newly added virtual columns along with indexes
  @param[in]	col_map		mapping of old column numbers to new ones, or
  NULL if old_table == new_table
  @param[in]	add_autoinc	number of added AUTO_INCREMENT columns, or
  ULINT_UNDEFINED if none is added
  @param[in,out]	sequence	autoinc sequence
  @param[in,out]	block		file buffer
  @param[in]	skip_pk_sort	whether the new PRIMARY KEY will follow
  existing order
  @param[in,out]	tmpfd		temporary file handle
  @param[in,out]	stage		performance schema accounting object, used by
  ALTER TABLE. stage->n_pk_recs_inc() will be called for each record read and
  stage->inc() will be called for each page read.
  @param[in]	pct_cost	percent of task weight out of total alter job
  @param[in,out]	crypt_block	crypted file buffer
  @param[in]	eval_table	mysql table used to evaluate virtual column
  				value, see innobase_get_computed_value().
  @param[in]	allow_not_null	allow null to not-null conversion
  @return DB_SUCCESS or error */
  static MY_ATTRIBUTE((warn_unused_result))
  dberr_t
  row_merge_read_clustered_index(
  	trx_t*			trx,
  	struct TABLE*		table,
  	const dict_table_t*	old_table,
  	dict_table_t*		new_table,
  	bool			online,
  	dict_index_t**		index,
  	dict_index_t*		fts_sort_idx,
  	fts_psort_t*		psort_info,
  	merge_file_t*		files,
  	const ulint*		key_numbers,
  	ulint			n_index,
  	const dtuple_t*		defaults,
  	const dict_add_v_col_t*	add_v,
  	const ulint*		col_map,
  	ulint			add_autoinc,
  	ib_sequence_t&		sequence,
  	row_merge_block_t*	block,
  	bool			skip_pk_sort,
  	pfs_os_file_t*			tmpfd,
  	ut_stage_alter_t*	stage,
  	double 			pct_cost,
  	row_merge_block_t*	crypt_block,
  	struct TABLE*		eval_table,
  	bool			allow_not_null)
  {
  	dict_index_t*		clust_index;	/* Clustered index */
  	mem_heap_t*		row_heap;	/* Heap memory to create
  						clustered index tuples */
  	row_merge_buf_t**	merge_buf;	/* Temporary list for records*/
  	mem_heap_t*		v_heap = NULL;	/* Heap memory to process large
  						data for virtual column */
  	btr_pcur_t		pcur;		/* Cursor on the clustered
  						index */
  	mtr_t			mtr;		/* Mini transaction */
  	dberr_t			err = DB_SUCCESS;/* Return code */
  	ulint			n_nonnull = 0;	/* number of columns
  						changed to NOT NULL */
  	ulint*			nonnull = NULL;	/* NOT NULL columns */
  	dict_index_t*		fts_index = NULL;/* FTS index */
  	doc_id_t		doc_id = 0;
  	doc_id_t		max_doc_id = 0;
  	ibool			add_doc_id = FALSE;
  	os_event_t		fts_parallel_sort_event = NULL;
  	ibool			fts_pll_sort = FALSE;
  	int64_t			sig_count = 0;
  	index_tuple_info_t**	sp_tuples = NULL;
  	mem_heap_t*		sp_heap = NULL;
  	ulint			num_spatial = 0;
  	BtrBulk*		clust_btr_bulk = NULL;
  	bool			clust_temp_file = false;
  	mem_heap_t*		mtuple_heap = NULL;
  	mtuple_t		prev_mtuple;
  	mem_heap_t*		conv_heap = NULL;
  	FlushObserver*		observer = trx->flush_observer;
  	double 			curr_progress = 0.0;
  	ib_uint64_t		read_rows = 0;
  	ib_uint64_t		table_total_rows = 0;
  	char			new_sys_trx_start[8];
  	char			new_sys_trx_end[8];
  	byte			any_autoinc_data[8] = {0};
  	bool			vers_update_trt = false;
  
  	DBUG_ENTER("row_merge_read_clustered_index");
  
  	ut_ad((old_table == new_table) == !col_map);
  	ut_ad(!defaults || col_map);
  	ut_ad(trx_state_eq(trx, TRX_STATE_ACTIVE));
  	ut_ad(trx->id);
  
  	table_total_rows = dict_table_get_n_rows(old_table);
  	if(table_total_rows == 0) {
  		/* We don't know total row count */
  		table_total_rows = 1;
  	}
  
  	trx->op_info = "reading clustered index";
  
  #ifdef FTS_INTERNAL_DIAG_PRINT
  	DEBUG_FTS_SORT_PRINT("FTS_SORT: Start Create Index\n");
  #endif
  
  	/* Create and initialize memory for record buffers */
  
  	merge_buf = static_cast<row_merge_buf_t**>(
  		ut_malloc_nokey(n_index * sizeof *merge_buf));
  
  	row_merge_dup_t	clust_dup = {index[0], table, col_map, 0};
  	dfield_t*	prev_fields;
  	const ulint	n_uniq = dict_index_get_n_unique(index[0]);
  
  	ut_ad(trx->mysql_thd != NULL);
  
  	const char*	path = thd_innodb_tmpdir(trx->mysql_thd);
  
  	ut_ad(!skip_pk_sort || dict_index_is_clust(index[0]));
  	/* There is no previous tuple yet. */
  	prev_mtuple.fields = NULL;
  
  	for (ulint i = 0; i < n_index; i++) {
  		if (index[i]->type & DICT_FTS) {
  
  			/* We are building a FT index, make sure
  			we have the temporary 'fts_sort_idx' */
  			ut_a(fts_sort_idx);
  
  			fts_index = index[i];
  
  			merge_buf[i] = row_merge_buf_create(fts_sort_idx);
  
  			add_doc_id = DICT_TF2_FLAG_IS_SET(
  				new_table, DICT_TF2_FTS_ADD_DOC_ID);
  
  			/* If Doc ID does not exist in the table itself,
  			fetch the first FTS Doc ID */
  			if (add_doc_id) {
  				fts_get_next_doc_id(
  					(dict_table_t*) new_table,
  					&doc_id);
  				ut_ad(doc_id > 0);
  			}
  
  			fts_pll_sort = TRUE;
  			row_fts_start_psort(psort_info);
  			fts_parallel_sort_event =
  				 psort_info[0].psort_common->sort_event;
  		} else {
  			if (dict_index_is_spatial(index[i])) {
  				num_spatial++;
  			}
  
  			merge_buf[i] = row_merge_buf_create(index[i]);
  		}
  	}
  
  	if (num_spatial > 0) {
  		ulint	count = 0;
  
  		sp_heap = mem_heap_create(512);
  
  		sp_tuples = static_cast<index_tuple_info_t**>(
  			ut_malloc_nokey(num_spatial
  					* sizeof(*sp_tuples)));
  
  		for (ulint i = 0; i < n_index; i++) {
  			if (dict_index_is_spatial(index[i])) {
  				sp_tuples[count]
  					= UT_NEW_NOKEY(
  						index_tuple_info_t(
  							sp_heap,
  							index[i]));
  				count++;
  			}
  		}
  
  		ut_ad(count == num_spatial);
  	}
  
  	mtr_start(&mtr);
  
  	/* Find the clustered index and create a persistent cursor
  	based on that. */
  
  	clust_index = dict_table_get_first_index(old_table);
  	const ulint old_trx_id_col = DATA_TRX_ID - DATA_N_SYS_COLS
  		+ ulint(old_table->n_cols);
  	ut_ad(old_table->cols[old_trx_id_col].mtype == DATA_SYS);
  	ut_ad(old_table->cols[old_trx_id_col].prtype
  	      == (DATA_TRX_ID | DATA_NOT_NULL));
  	ut_ad(old_table->cols[old_trx_id_col + 1].mtype == DATA_SYS);
  	ut_ad(old_table->cols[old_trx_id_col + 1].prtype
  	      == (DATA_ROLL_PTR | DATA_NOT_NULL));
  	const ulint new_trx_id_col = col_map
  		? col_map[old_trx_id_col] : old_trx_id_col;
  
  	btr_pcur_open_at_index_side(
  		true, clust_index, BTR_SEARCH_LEAF, &pcur, true, 0, &mtr);
  	btr_pcur_move_to_next_user_rec(&pcur, &mtr);
  	if (rec_is_default_row(btr_pcur_get_rec(&pcur), clust_index)) {
  		ut_ad(btr_pcur_is_on_user_rec(&pcur));
  		/* Skip the 'default row' pseudo-record. */
  	} else {
  		ut_ad(!clust_index->is_instant());
  		btr_pcur_move_to_prev_on_page(&pcur);
  	}
  
  	if (old_table != new_table) {
  		/* The table is being rebuilt.  Identify the columns
  		that were flagged NOT NULL in the new table, so that
  		we can quickly check that the records in the old table
  		do not violate the added NOT NULL constraints. */
  
  		nonnull = static_cast<ulint*>(
  			ut_malloc_nokey(dict_table_get_n_cols(new_table)
  				  * sizeof *nonnull));
  
  		for (ulint i = 0; i < dict_table_get_n_cols(old_table); i++) {
  			if (dict_table_get_nth_col(old_table, i)->prtype
  			    & DATA_NOT_NULL) {
  				continue;
  			}
  
  			const ulint j = col_map[i];
  
  			if (j == ULINT_UNDEFINED) {
  				/* The column was dropped. */
  				continue;
  			}
  
  			if (dict_table_get_nth_col(new_table, j)->prtype
  			    & DATA_NOT_NULL) {
  				nonnull[n_nonnull++] = j;
  			}
  		}
  
  		if (!n_nonnull) {
  			ut_free(nonnull);
  			nonnull = NULL;
  		}
  	}
  
  	row_heap = mem_heap_create(sizeof(mrec_buf_t));
  
  	if (dict_table_is_comp(old_table)
  	    && !dict_table_is_comp(new_table)) {
  		conv_heap = mem_heap_create(sizeof(mrec_buf_t));
  	}
  
  	if (skip_pk_sort) {
  		prev_fields = static_cast<dfield_t*>(
  			ut_malloc_nokey(n_uniq * sizeof *prev_fields));
  		mtuple_heap = mem_heap_create(sizeof(mrec_buf_t));
  	} else {
  		prev_fields = NULL;
  	}
  
  	mach_write_to_8(new_sys_trx_start, trx->id);
  	mach_write_to_8(new_sys_trx_end, TRX_ID_MAX);
  	uint64_t	n_rows = 0;
  
  	/* Scan the clustered index. */
  	for (;;) {
  		const rec_t*	rec;
  		trx_id_t	rec_trx_id;
  		ulint*		offsets;
  		const dtuple_t*	row;
  		row_ext_t*	ext;
  		page_cur_t*	cur	= btr_pcur_get_page_cur(&pcur);
  
  		mem_heap_empty(row_heap);
  
  		/* Do not continue if table pages are still encrypted */
  		if (!old_table->is_readable() ||
  		    !new_table->is_readable()) {
  			err = DB_DECRYPTION_FAILED;
  			trx->error_key_num = 0;
  			goto func_exit;
  		}
  
  		mem_heap_empty(row_heap);
  
  		page_cur_move_to_next(cur);
  
  		stage->n_pk_recs_inc();
  
  		if (page_cur_is_after_last(cur)) {
  
  			stage->inc();
  
  			if (UNIV_UNLIKELY(trx_is_interrupted(trx))) {
  				err = DB_INTERRUPTED;
  				trx->error_key_num = 0;
  				goto func_exit;
  			}
  
  			if (online && old_table != new_table) {
  				err = row_log_table_get_error(clust_index);
  				if (err != DB_SUCCESS) {
  					trx->error_key_num = 0;
  					goto func_exit;
  				}
  			}
  
  			/* Insert the cached spatial index rows. */
  			bool	mtr_committed = false;
  
  			err = row_merge_spatial_rows(
  				trx->id, sp_tuples, num_spatial,
  				row_heap, sp_heap, &pcur,
  				&mtr, &mtr_committed);
  
  			if (err != DB_SUCCESS) {
  				goto func_exit;
  			}
  
  			if (mtr_committed) {
  				goto scan_next;
  			}
  
  			if (my_atomic_load32_explicit(&clust_index->lock.waiters,
  						      MY_MEMORY_ORDER_RELAXED)) {
  				/* There are waiters on the clustered
  				index tree lock, likely the purge
  				thread. Store and restore the cursor
  				position, and yield so that scanning a
  				large table will not starve other
  				threads. */
  
  				/* Store the cursor position on the last user
  				record on the page. */
  				btr_pcur_move_to_prev_on_page(&pcur);
  				/* Leaf pages must never be empty, unless
  				this is the only page in the index tree. */
  				ut_ad(btr_pcur_is_on_user_rec(&pcur)
  				      || btr_pcur_get_block(
  					      &pcur)->page.id.page_no()
  				      == clust_index->page);
  
  				btr_pcur_store_position(&pcur, &mtr);
  				mtr_commit(&mtr);
  
  				/* Give the waiters a chance to proceed. */
  				os_thread_yield();
  scan_next:
  				mtr_start(&mtr);
  				/* Restore position on the record, or its
  				predecessor if the record was purged
  				meanwhile. */
  				btr_pcur_restore_position(
  					BTR_SEARCH_LEAF, &pcur, &mtr);
  				/* Move to the successor of the
  				original record. */
  				if (!btr_pcur_move_to_next_user_rec(
  					    &pcur, &mtr)) {
  end_of_index:
  					row = NULL;
  					mtr_commit(&mtr);
  					mem_heap_free(row_heap);
  					ut_free(nonnull);
  					goto write_buffers;
  				}
  			} else {
  				ulint		next_page_no;
  				buf_block_t*	block;
  
  				next_page_no = btr_page_get_next(
  					page_cur_get_page(cur), &mtr);
  
  				if (next_page_no == FIL_NULL) {
  					goto end_of_index;
  				}
  
  				block = page_cur_get_block(cur);
  				block = btr_block_get(
  					page_id_t(block->page.id.space(),
  						  next_page_no),
  					block->page.size,
  					BTR_SEARCH_LEAF,
  					clust_index, &mtr);
  
  				btr_leaf_page_release(page_cur_get_block(cur),
  						      BTR_SEARCH_LEAF, &mtr);
  				page_cur_set_before_first(block, cur);
  				page_cur_move_to_next(cur);
  
  				ut_ad(!page_cur_is_after_last(cur));
  			}
  		}
  
  		rec = page_cur_get_rec(cur);
  
  		if (online) {
  			offsets = rec_get_offsets(rec, clust_index, NULL, true,
  						  ULINT_UNDEFINED, &row_heap);
  			rec_trx_id = row_get_rec_trx_id(rec, clust_index,
  							offsets);
  
  			/* Perform a REPEATABLE READ.
  
  			When rebuilding the table online,
  			row_log_table_apply() must not see a newer
  			state of the table when applying the log.
  			This is mainly to prevent false duplicate key
  			errors, because the log will identify records
  			by the PRIMARY KEY, and also to prevent unsafe
  			BLOB access.
  
  			When creating a secondary index online, this
  			table scan must not see records that have only
  			been inserted to the clustered index, but have
  			not been written to the online_log of
  			index[]. If we performed READ UNCOMMITTED, it
  			could happen that the ADD INDEX reaches
  			ONLINE_INDEX_COMPLETE state between the time
  			the DML thread has updated the clustered index
  			but has not yet accessed secondary index. */
  			ut_ad(trx->read_view.is_open());
  			ut_ad(rec_trx_id != trx->id);
  
  			if (!trx->read_view.changes_visible(
  				    rec_trx_id, old_table->name)) {
  				rec_t*	old_vers;
  
  				row_vers_build_for_consistent_read(
  					rec, &mtr, clust_index, &offsets,
  					&trx->read_view, &row_heap,
  					row_heap, &old_vers, NULL);
  
  				if (!old_vers) {
  					continue;
  				}
  
  				/* The old version must necessarily be
  				in the "prehistory", because the
  				exclusive lock in
  				ha_innobase::prepare_inplace_alter_table()
  				forced the completion of any transactions
  				that accessed this table. */
  				ut_ad(row_get_rec_trx_id(old_vers, clust_index,
  							 offsets) < trx->id);
  
  				rec = old_vers;
  				rec_trx_id = 0;
  			}
  
  			if (rec_get_deleted_flag(
  				    rec,
  				    dict_table_is_comp(old_table))) {
  				/* In delete-marked records, DB_TRX_ID must
  				always refer to an existing undo log record.
  				Above, we did reset rec_trx_id = 0
  				for rec = old_vers.*/
  				ut_ad(rec == page_cur_get_rec(cur)
  				      ? rec_trx_id
  				      : !rec_trx_id);
  				/* This record was deleted in the latest
  				committed version, or it was deleted and
  				then reinserted-by-update before purge
  				kicked in. Skip it. */
  				continue;
  			}
  
  			ut_ad(!rec_offs_any_null_extern(rec, offsets));
  		} else if (rec_get_deleted_flag(
  				   rec, dict_table_is_comp(old_table))) {
  			/* In delete-marked records, DB_TRX_ID must
  			always refer to an existing undo log record. */
  			ut_d(rec_trx_id = rec_get_trx_id(rec, clust_index));
  			ut_ad(rec_trx_id);
  			/* This must be a purgeable delete-marked record,
  			and the transaction that delete-marked the record
  			must have been committed before this
  			!online ALTER TABLE transaction. */
  			ut_ad(rec_trx_id < trx->id);
  			/* Skip delete-marked records.
  
  			Skipping delete-marked records will make the
  			created indexes unuseable for transactions
  			whose read views were created before the index
  			creation completed, but an attempt to preserve
  			the history would make it tricky to detect
  			duplicate keys. */
  			continue;
  		} else {
  			offsets = rec_get_offsets(rec, clust_index, NULL, true,
  						  ULINT_UNDEFINED, &row_heap);
  			/* This is a locking ALTER TABLE.
  
  			If we are not rebuilding the table, the
  			DB_TRX_ID does not matter, as it is not being
  			written to any secondary indexes; see
  			if (old_table == new_table) below.
  
  			If we are rebuilding the table, the
  			DB_TRX_ID,DB_ROLL_PTR should be reset, because
  			there will be no history available. */
  			ut_ad(rec_get_trx_id(rec, clust_index) < trx->id);
  			rec_trx_id = 0;
  		}
  
  		/* When !online, we are holding a lock on old_table, preventing
  		any inserts that could have written a record 'stub' before
  		writing out off-page columns. */
  		ut_ad(!rec_offs_any_null_extern(rec, offsets));
  
  		/* Build a row based on the clustered index. */
  
  		row = row_build_w_add_vcol(ROW_COPY_POINTERS, clust_index,
  					   rec, offsets, new_table,
  					   defaults, add_v, col_map, &ext,
  					   row_heap);
  		ut_ad(row);
  
  		for (ulint i = 0; i < n_nonnull; i++) {
  			dfield_t*	field	= &row->fields[nonnull[i]];
  
  			ut_ad(dfield_get_type(field)->prtype & DATA_NOT_NULL);
  
  			if (dfield_is_null(field)) {
  
  				Field* null_field =
  					table->field[nonnull[i]];
  
  				null_field->set_warning(
  					Sql_condition::WARN_LEVEL_WARN,
  					WARN_DATA_TRUNCATED, 1,
  					ulong(n_rows + 1));
  
  				if (!allow_not_null) {
  					err = DB_INVALID_NULL;
  					trx->error_key_num = 0;
  					goto func_exit;
  				}
  
  				const dfield_t& default_field
  					= defaults->fields[nonnull[i]];
  
  				*field = default_field;
  			}
  		}
  
  		/* Get the next Doc ID */
  		if (add_doc_id) {
  			doc_id++;
  		} else {
  			doc_id = 0;
  		}
  
  		ut_ad(row->fields[new_trx_id_col].type.mtype == DATA_SYS);
  		ut_ad(row->fields[new_trx_id_col].type.prtype
  		      == (DATA_TRX_ID | DATA_NOT_NULL));
  		ut_ad(row->fields[new_trx_id_col].len == DATA_TRX_ID_LEN);
  		ut_ad(row->fields[new_trx_id_col + 1].type.mtype == DATA_SYS);
  		ut_ad(row->fields[new_trx_id_col + 1].type.prtype
  		      == (DATA_ROLL_PTR | DATA_NOT_NULL));
  		ut_ad(row->fields[new_trx_id_col + 1].len == DATA_ROLL_PTR_LEN);
  
  		if (old_table == new_table) {
  			/* Do not bother touching DB_TRX_ID,DB_ROLL_PTR
  			because they are not going to be written into
  			secondary indexes. */
  		} else if (rec_trx_id < trx->id) {
  			/* Reset the DB_TRX_ID,DB_ROLL_PTR of old rows
  			for which history is not going to be
  			available after the rebuild operation.
  			This essentially mimics row_purge_reset_trx_id(). */
  			row->fields[new_trx_id_col].data
  				= const_cast<byte*>(reset_trx_id);
  			row->fields[new_trx_id_col + 1].data
  				= const_cast<byte*>(reset_trx_id
  						    + DATA_TRX_ID_LEN);
  		}
  
  		if (add_autoinc != ULINT_UNDEFINED) {
  
  			ut_ad(add_autoinc
  			      < dict_table_get_n_user_cols(new_table));
  
  			bool history_row = false;
  			if (new_table->versioned()) {
  				const dfield_t* dfield = dtuple_get_nth_field(
  				    row, new_table->vers_end);
  				history_row = dfield->vers_history_row();
  			}
  
  			dfield_t*	dfield;
  
  			dfield = dtuple_get_nth_field(row, add_autoinc);
  
  			if (new_table->versioned()) {
  				if (history_row) {
  					if (dfield_get_type(dfield)->prtype & DATA_NOT_NULL) {
  						err = DB_UNSUPPORTED;
  						my_error(ER_UNSUPPORTED_EXTENSION, MYF(0),
  							 old_table->name.m_name);
  						goto func_exit;
  					}
  					dfield_set_null(dfield);
  				} else {
  					// set not null
  					ulint len = dfield_get_type(dfield)->len;
  					dfield_set_data(dfield, any_autoinc_data, len);
  				}
  			}
  
  			if (dfield_is_null(dfield)) {
  				goto write_buffers;
  			}
  
  			const dtype_t*  dtype = dfield_get_type(dfield);
  			byte*	b = static_cast<byte*>(dfield_get_data(dfield));
  
  			if (sequence.eof()) {
  				err = DB_ERROR;
  				trx->error_key_num = 0;
  
  				ib_errf(trx->mysql_thd, IB_LOG_LEVEL_ERROR,
  					ER_AUTOINC_READ_FAILED, "[NULL]");
  
  				goto func_exit;
  			}
  
  			ulonglong	value = sequence++;
  
  			switch (dtype_get_mtype(dtype)) {
  			case DATA_INT: {
  				ibool	usign;
  				ulint	len = dfield_get_len(dfield);
  
  				usign = dtype_get_prtype(dtype) & DATA_UNSIGNED;
  				mach_write_ulonglong(b, value, len, usign);
  
  				break;
  				}
  
  			case DATA_FLOAT:
  				mach_float_write(
  					b, static_cast<float>(value));
  				break;
  
  			case DATA_DOUBLE:
  				mach_double_write(
  					b, static_cast<double>(value));
  				break;
  
  			default:
  				ut_ad(0);
  			}
  		}
  
  		if (old_table->versioned()) {
  			if (!new_table->versioned()
  			    && clust_index->vers_history_row(rec, offsets)) {
  				continue;
  			}
  		} else if (new_table->versioned()) {
  			dfield_t* start =
  			    dtuple_get_nth_field(row, new_table->vers_start);
  			dfield_t* end =
  			    dtuple_get_nth_field(row, new_table->vers_end);
  			dfield_set_data(start, new_sys_trx_start, 8);
  			dfield_set_data(end, new_sys_trx_end, 8);
  			vers_update_trt = true;
  		}
  
  write_buffers:
  		/* Build all entries for all the indexes to be created
  		in a single scan of the clustered index. */
  
  		n_rows++;
  		ulint	s_idx_cnt = 0;
  		bool	skip_sort = skip_pk_sort
  			&& dict_index_is_clust(merge_buf[0]->index);
  
  		for (ulint i = 0; i < n_index; i++, skip_sort = false) {
  			row_merge_buf_t*	buf	= merge_buf[i];
  			merge_file_t*		file	= &files[i];
  			ulint			rows_added = 0;
  
  			if (dict_index_is_spatial(buf->index)) {
  				if (!row) {
  					continue;
  				}
  
  				ut_ad(sp_tuples[s_idx_cnt]->get_index()
  				      == buf->index);
  
  				/* If the geometry field is invalid, report
  				error. */
  				if (!row_geo_field_is_valid(row, buf->index)) {
  					err = DB_CANT_CREATE_GEOMETRY_OBJECT;
  					break;
  				}
  
  				sp_tuples[s_idx_cnt]->add(row, ext);
  				s_idx_cnt++;
  
  				continue;
  			}
  
  			ut_ad(!row
  			      || !dict_index_is_clust(buf->index)
  			      || trx_id_check(row->fields[new_trx_id_col].data,
  					      trx->id));
  
  			if (UNIV_LIKELY
  			    (row && (rows_added = row_merge_buf_add(
  					buf, fts_index, old_table, new_table,
  					psort_info, row, ext, &doc_id,
  					conv_heap, &err,
  					&v_heap, eval_table, trx)))) {
  
  				/* If we are creating FTS index,
  				a single row can generate more
  				records for tokenized word */
  				file->n_rec += rows_added;
  
  				if (err != DB_SUCCESS) {
  					ut_ad(err == DB_TOO_BIG_RECORD);
  					break;
  				}
  
  				if (doc_id > max_doc_id) {
  					max_doc_id = doc_id;
  				}
  
  				if (buf->index->type & DICT_FTS) {
  					/* Check if error occurs in child thread */
  					for (ulint j = 0;
  					     j < fts_sort_pll_degree; j++) {
  						if (psort_info[j].error
  							!= DB_SUCCESS) {
  							err = psort_info[j].error;
  							trx->error_key_num = i;
  							break;
  						}
  					}
  
  					if (err != DB_SUCCESS) {
  						break;
  					}
  				}
  
  				if (skip_sort) {
  					ut_ad(buf->n_tuples > 0);
  					const mtuple_t*	curr =
  						&buf->tuples[buf->n_tuples - 1];
  
  					ut_ad(i == 0);
  					ut_ad(dict_index_is_clust(merge_buf[0]->index));
  					/* Detect duplicates by comparing the
  					current record with previous record.
  					When temp file is not used, records
  					should be in sorted order. */
  					if (prev_mtuple.fields != NULL
  					    && (row_mtuple_cmp(
  						&prev_mtuple, curr,
  						&clust_dup) == 0)) {
  
  						err = DB_DUPLICATE_KEY;
  						trx->error_key_num
  							= key_numbers[0];
  						goto func_exit;
  					}
  
  					prev_mtuple.fields = curr->fields;
  				}
  
  				continue;
  			}
  
  			if (err == DB_COMPUTE_VALUE_FAILED) {
  				trx->error_key_num = i;
  				goto func_exit;
  			}
  
  			if (buf->index->type & DICT_FTS) {
  				if (!row || !doc_id) {
  					continue;
  				}
  			}
  
  			/* The buffer must be sufficiently large
  			to hold at least one record. It may only
  			be empty when we reach the end of the
  			clustered index. row_merge_buf_add()
  			must not have been called in this loop. */
  			ut_ad(buf->n_tuples || row == NULL);
  
  			/* We have enough data tuples to form a block.
  			Sort them and write to disk if temp file is used
  			or insert into index if temp file is not used. */
  			ut_ad(old_table == new_table
  			      ? !dict_index_is_clust(buf->index)
  			      : (i == 0) == dict_index_is_clust(buf->index));
  
  			/* We have enough data tuples to form a block.
  			Sort them (if !skip_sort) and write to disk. */
  
  			if (buf->n_tuples) {
  				if (skip_sort) {
  					/* Temporary File is not used.
  					so insert sorted block to the index */
  					if (row != NULL) {
  						bool	mtr_committed = false;
  
  						/* We have to do insert the
  						cached spatial index rows, since
  						after the mtr_commit, the cluster
  						index page could be updated, then
  						the data in cached rows become
  						invalid. */
  						err = row_merge_spatial_rows(
  							trx->id, sp_tuples,
  							num_spatial,
  							row_heap, sp_heap,
  							&pcur, &mtr,
  							&mtr_committed);
  
  						if (err != DB_SUCCESS) {
  							goto func_exit;
  						}
  
  						/* We are not at the end of
  						the scan yet. We must
  						mtr_commit() in order to be
  						able to call log_free_check()
  						in row_merge_insert_index_tuples().
  						Due to mtr_commit(), the
  						current row will be invalid, and
  						we must reread it on the next
  						loop iteration. */
  						if (!mtr_committed) {
  							btr_pcur_move_to_prev_on_page(
  								&pcur);
  							btr_pcur_store_position(
  								&pcur, &mtr);
  
  							mtr_commit(&mtr);
  						}
  					}
  
  					mem_heap_empty(mtuple_heap);
  					prev_mtuple.fields = prev_fields;
  
  					row_mtuple_create(
  						&buf->tuples[buf->n_tuples - 1],
  						&prev_mtuple, n_uniq,
  						mtuple_heap);
  
  					if (clust_btr_bulk == NULL) {
  						clust_btr_bulk = UT_NEW_NOKEY(
  							BtrBulk(index[i],
  								trx->id,
  								observer));
  
  						clust_btr_bulk->init();
  					} else {
  						clust_btr_bulk->latch();
  					}
  
  					err = row_merge_insert_index_tuples(
  						index[i], old_table,
  						OS_FILE_CLOSED, NULL, buf, clust_btr_bulk,
  						table_total_rows,
  						curr_progress,
  						pct_cost,
  						crypt_block,
  						new_table->space->id);
  
  					if (row == NULL) {
  						err = clust_btr_bulk->finish(
  							err);
  						UT_DELETE(clust_btr_bulk);
  						clust_btr_bulk = NULL;
  					} else {
  						/* Release latches for possible
  						log_free_chck in spatial index
  						build. */
  						clust_btr_bulk->release();
  					}
  
  					if (err != DB_SUCCESS) {
  						break;
  					}
  
  					if (row != NULL) {
  						/* Restore the cursor on the
  						previous clustered index record,
  						and empty the buffer. The next
  						iteration of the outer loop will
  						advance the cursor and read the
  						next record (the one which we
  						had to ignore due to the buffer
  						overflow). */
  						mtr_start(&mtr);
  						btr_pcur_restore_position(
  							BTR_SEARCH_LEAF, &pcur,
  							&mtr);
  						buf = row_merge_buf_empty(buf);
  						/* Restart the outer loop on the
  						record. We did not insert it
  						into any index yet. */
  						ut_ad(i == 0);
  						break;
  					}
  				} else if (dict_index_is_unique(buf->index)) {
  					row_merge_dup_t	dup = {
  						buf->index, table, col_map, 0};
  
  					row_merge_buf_sort(buf, &dup);
  
  					if (dup.n_dup) {
  						err = DB_DUPLICATE_KEY;
  						trx->error_key_num
  							= key_numbers[i];
  						break;
  					}
  				} else {
  					row_merge_buf_sort(buf, NULL);
  				}
  			} else if (online && new_table == old_table) {
  				/* Note the newest transaction that
  				modified this index when the scan was
  				completed. We prevent older readers
  				from accessing this index, to ensure
  				read consistency. */
  
  				trx_id_t	max_trx_id;
  
  				ut_a(row == NULL);
  				rw_lock_x_lock(
  					dict_index_get_lock(buf->index));
  				ut_a(dict_index_get_online_status(buf->index)
  				     == ONLINE_INDEX_CREATION);
  
  				max_trx_id = row_log_get_max_trx(buf->index);
  
  				if (max_trx_id > buf->index->trx_id) {
  					buf->index->trx_id = max_trx_id;
  				}
  
  				rw_lock_x_unlock(
  					dict_index_get_lock(buf->index));
  			}
  
  			/* Secondary index and clustered index which is
  			not in sorted order can use the temporary file.
  			Fulltext index should not use the temporary file. */
  			if (!skip_sort && !(buf->index->type & DICT_FTS)) {
  				/* In case we can have all rows in sort buffer,
  				we can insert directly into the index without
  				temporary file if clustered index does not uses
  				temporary file. */
  				if (row == NULL && file->fd == OS_FILE_CLOSED
  				    && !clust_temp_file) {
  					DBUG_EXECUTE_IF(
  						"row_merge_write_failure",
  						err = DB_TEMP_FILE_WRITE_FAIL;
  						trx->error_key_num = i;
  						goto all_done;);
  
  					DBUG_EXECUTE_IF(
  						"row_merge_tmpfile_fail",
  						err = DB_OUT_OF_MEMORY;
  						trx->error_key_num = i;
  						goto all_done;);
  
  					BtrBulk	btr_bulk(index[i], trx->id,
  							 observer);
  					btr_bulk.init();
  
  					err = row_merge_insert_index_tuples(
  						index[i], old_table,
  						OS_FILE_CLOSED, NULL, buf, &btr_bulk,
  						table_total_rows,
  						curr_progress,
  						pct_cost,
  						crypt_block,
  						new_table->space->id);
  
  					err = btr_bulk.finish(err);
  
  					DBUG_EXECUTE_IF(
  						"row_merge_insert_big_row",
  						err = DB_TOO_BIG_RECORD;);
  
  					if (err != DB_SUCCESS) {
  						break;
  					}
  				} else {
  					if (!row_merge_file_create_if_needed(
  						file, tmpfd,
  						buf->n_tuples, path)) {
  						err = DB_OUT_OF_MEMORY;
  						trx->error_key_num = i;
  						goto func_exit;
  					}
  
  					/* Ensure that duplicates in the
  					clustered index will be detected before
  					inserting secondary index records. */
  					if (dict_index_is_clust(buf->index)) {
  						clust_temp_file = true;
  					}
  
  					ut_ad(file->n_rec > 0);
  
  					row_merge_buf_write(buf, file, block);
  
  					if (!row_merge_write(
  						    file->fd, file->offset++,
  						    block, crypt_block,
  						    new_table->space->id)) {
  						err = DB_TEMP_FILE_WRITE_FAIL;
  						trx->error_key_num = i;
  						break;
  					}
  
  					UNIV_MEM_INVALID(
  						&block[0], srv_sort_buf_size);
  				}
  			}
  			merge_buf[i] = row_merge_buf_empty(buf);
  
  			if (UNIV_LIKELY(row != NULL)) {
  				/* Try writing the record again, now
  				that the buffer has been written out
  				and emptied. */
  
  				if (UNIV_UNLIKELY
  				    (!(rows_added = row_merge_buf_add(
  						buf, fts_index, old_table,
  						new_table, psort_info, row, ext,
  						&doc_id, conv_heap,
  						&err, &v_heap, table, trx)))) {
  					/* An empty buffer should have enough
  					room for at least one record. */
  					ut_error;
  				}
  
  				if (err != DB_SUCCESS) {
  					break;
  				}
  
  				file->n_rec += rows_added;
  			}
  		}
  
  		if (row == NULL) {
  			if (old_table != new_table) {
  				new_table->stat_n_rows = n_rows;
  			}
  
  			goto all_done;
  		}
  
  		if (err != DB_SUCCESS) {
  			goto func_exit;
  		}
  
  		if (v_heap) {
  			mem_heap_empty(v_heap);
  		}
  
  		/* Increment innodb_onlineddl_pct_progress status variable */
  		read_rows++;
  		if(read_rows % 1000 == 0) {
  			/* Update progress for each 1000 rows */
  			curr_progress = (read_rows >= table_total_rows) ?
  					pct_cost :
  				((pct_cost * read_rows) / table_total_rows);
  			/* presenting 10.12% as 1012 integer */
  			onlineddl_pct_progress = (ulint) (curr_progress * 100);
  		}
  	}
  
  func_exit:
  	/* row_merge_spatial_rows may have committed
  	the mtr	before an error occurs. */
  	if (mtr.is_active()) {
  		mtr_commit(&mtr);
  	}
  	mem_heap_free(row_heap);
  	ut_free(nonnull);
  
  all_done:
  	if (clust_btr_bulk != NULL) {
  		ut_ad(err != DB_SUCCESS);
  		clust_btr_bulk->latch();
  		err = clust_btr_bulk->finish(
  			err);
  		UT_DELETE(clust_btr_bulk);
  	}
  
  	if (prev_fields != NULL) {
  		ut_free(prev_fields);
  		mem_heap_free(mtuple_heap);
  	}
  
  	if (v_heap) {
  		mem_heap_free(v_heap);
  	}
  
  	if (conv_heap != NULL) {
  		mem_heap_free(conv_heap);
  	}
  
  #ifdef FTS_INTERNAL_DIAG_PRINT
  	DEBUG_FTS_SORT_PRINT("FTS_SORT: Complete Scan Table\n");
  #endif
  	if (fts_pll_sort) {
  		bool	all_exit = false;
  		ulint	trial_count = 0;
  		const ulint max_trial_count = 10000;
  
  wait_again:
                  /* Check if error occurs in child thread */
  		for (ulint j = 0; j < fts_sort_pll_degree; j++) {
  			if (psort_info[j].error != DB_SUCCESS) {
  				err = psort_info[j].error;
  				trx->error_key_num = j;
  				break;
  			}
  		}
  
  		/* Tell all children that parent has done scanning */
  		for (ulint i = 0; i < fts_sort_pll_degree; i++) {
  			if (err == DB_SUCCESS) {
  				psort_info[i].state = FTS_PARENT_COMPLETE;
  			} else {
  				psort_info[i].state = FTS_PARENT_EXITING;
  			}
  		}
  
  		/* Now wait all children to report back to be completed */
  		os_event_wait_time_low(fts_parallel_sort_event,
  				       1000000, sig_count);
  
  		for (ulint i = 0; i < fts_sort_pll_degree; i++) {
  			if (psort_info[i].child_status != FTS_CHILD_COMPLETE
  			    && psort_info[i].child_status != FTS_CHILD_EXITING) {
  				sig_count = os_event_reset(
  					fts_parallel_sort_event);
  				goto wait_again;
  			}
  		}
  
  		/* Now all children should complete, wait a bit until
  		they all finish setting the event, before we free everything.
  		This has a 10 second timeout */
  		do {
  			all_exit = true;
  
  			for (ulint j = 0; j < fts_sort_pll_degree; j++) {
  				if (psort_info[j].child_status
  				    != FTS_CHILD_EXITING) {
  					all_exit = false;
  					os_thread_sleep(1000);
  					break;
  				}
  			}
  			trial_count++;
  		} while (!all_exit && trial_count < max_trial_count);
  
  		if (!all_exit) {
  			ib::fatal() << "Not all child sort threads exited"
  				" when creating FTS index '"
  				<< fts_sort_idx->name << "'";
  		}
  	}
  
  #ifdef FTS_INTERNAL_DIAG_PRINT
  	DEBUG_FTS_SORT_PRINT("FTS_SORT: Complete Tokenization\n");
  #endif
  	for (ulint i = 0; i < n_index; i++) {
  		row_merge_buf_free(merge_buf[i]);
  	}
  
  	row_fts_free_pll_merge_buf(psort_info);
  
  	ut_free(merge_buf);
  
  	btr_pcur_close(&pcur);
  
  	if (sp_tuples != NULL) {
  		for (ulint i = 0; i < num_spatial; i++) {
  			UT_DELETE(sp_tuples[i]);
  		}
  		ut_free(sp_tuples);
  
  		if (sp_heap) {
  			mem_heap_free(sp_heap);
  		}
  	}
  
  	/* Update the next Doc ID we used. Table should be locked, so
  	no concurrent DML */
  	if (max_doc_id && err == DB_SUCCESS) {
  		/* Sync fts cache for other fts indexes to keep all
  		fts indexes consistent in sync_doc_id. */
  		err = fts_sync_table(const_cast<dict_table_t*>(new_table),
  				     false, true, false);
  
  		if (err == DB_SUCCESS) {
  			fts_update_next_doc_id(
  				0, new_table,
  				old_table->name.m_name, max_doc_id);
  		}
  	}
  
  	if (vers_update_trt) {
  		trx_mod_table_time_t& time =
  			trx->mod_tables
  				.insert(trx_mod_tables_t::value_type(
  					const_cast<dict_table_t*>(new_table), 0))
  				.first->second;
  		time.set_versioned(0);
  	}
  
  	trx->op_info = "";
  
  	DBUG_RETURN(err);
  }
  
  /** Write a record via buffer 2 and read the next record to buffer N.
  @param N number of the buffer (0 or 1)
  @param INDEX record descriptor
  @param AT_END statement to execute at end of input */
  #define ROW_MERGE_WRITE_GET_NEXT_LOW(N, INDEX, AT_END)			\
  	do {								\
  		b2 = row_merge_write_rec(&block[2 * srv_sort_buf_size], \
  					 &buf[2], b2,			\
  					 of->fd, &of->offset,		\
  					 mrec##N, offsets##N,		\
  			crypt_block ? &crypt_block[2 * srv_sort_buf_size] : NULL , \
  					space);				\
  		if (UNIV_UNLIKELY(!b2 || ++of->n_rec > file->n_rec)) {	\
  			goto corrupt;					\
  		}							\
  		b##N = row_merge_read_rec(&block[N * srv_sort_buf_size],\
  					  &buf[N], b##N, INDEX,		\
  					  file->fd, foffs##N,		\
  					  &mrec##N, offsets##N,		\
  			crypt_block ? &crypt_block[N * srv_sort_buf_size] : NULL, \
  					  space);			\
  									\
  		if (UNIV_UNLIKELY(!b##N)) {				\
  			if (mrec##N) {					\
  				goto corrupt;				\
  			}						\
  			AT_END;						\
  		}							\
  	} while (0)
  
  #ifdef HAVE_PSI_STAGE_INTERFACE
  #define ROW_MERGE_WRITE_GET_NEXT(N, INDEX, AT_END)			\
  	do {								\
  		if (stage != NULL) {					\
  			stage->inc();					\
  		}							\
  		ROW_MERGE_WRITE_GET_NEXT_LOW(N, INDEX, AT_END);		\
  	} while (0)
  #else /* HAVE_PSI_STAGE_INTERFACE */
  #define ROW_MERGE_WRITE_GET_NEXT(N, INDEX, AT_END)			\
  	ROW_MERGE_WRITE_GET_NEXT_LOW(N, INDEX, AT_END)
  #endif /* HAVE_PSI_STAGE_INTERFACE */
  
  /** Merge two blocks of records on disk and write a bigger block.
  @param[in]	dup	descriptor of index being created
  @param[in]	file	file containing index entries
  @param[in,out]	block	3 buffers
  @param[in,out]	foffs0	offset of first source list in the file
  @param[in,out]	foffs1	offset of second source list in the file
  @param[in,out]	of	output file
  @param[in,out]	stage	performance schema accounting object, used by
  ALTER TABLE. If not NULL stage->inc() will be called for each record
  processed.
  @param[in,out]	crypt_block	encryption buffer
  @param[in]	space	tablespace ID for encryption
  @return DB_SUCCESS or error code */
  static MY_ATTRIBUTE((warn_unused_result))
  dberr_t
  row_merge_blocks(
  	const row_merge_dup_t*	dup,
  	const merge_file_t*	file,
  	row_merge_block_t*	block,
  	ulint*			foffs0,
  	ulint*			foffs1,
  	merge_file_t*		of,
  	ut_stage_alter_t*	stage MY_ATTRIBUTE((unused)),
  	row_merge_block_t*	crypt_block,
  	ulint			space)
  {
  	mem_heap_t*	heap;	/*!< memory heap for offsets0, offsets1 */
  
  	mrec_buf_t*	buf;	/*!< buffer for handling
  				split mrec in block[] */
  	const byte*	b0;	/*!< pointer to block[0] */
  	const byte*	b1;	/*!< pointer to block[srv_sort_buf_size] */
  	byte*		b2;	/*!< pointer to block[2 * srv_sort_buf_size] */
  	const mrec_t*	mrec0;	/*!< merge rec, points to block[0] or buf[0] */
  	const mrec_t*	mrec1;	/*!< merge rec, points to
  				block[srv_sort_buf_size] or buf[1] */
  	ulint*		offsets0;/* offsets of mrec0 */
  	ulint*		offsets1;/* offsets of mrec1 */
  
  	DBUG_ENTER("row_merge_blocks");
  	DBUG_LOG("ib_merge_sort",
  		 "fd=" << file->fd << ',' << *foffs0 << '+' << *foffs1
  		 << " to fd=" << of->fd << ',' << of->offset);
  
  	heap = row_merge_heap_create(dup->index, &buf, &offsets0, &offsets1);
  
  	/* Write a record and read the next record.  Split the output
  	file in two halves, which can be merged on the following pass. */
  
  	if (!row_merge_read(file->fd, *foffs0, &block[0],
  			    crypt_block ? &crypt_block[0] : NULL,
  			    space) ||
  	    !row_merge_read(file->fd, *foffs1, &block[srv_sort_buf_size],
  			    crypt_block ? &crypt_block[srv_sort_buf_size] : NULL,
  			    space)) {
  corrupt:
  		mem_heap_free(heap);
  		DBUG_RETURN(DB_CORRUPTION);
  	}
  
  	b0 = &block[0];
  	b1 = &block[srv_sort_buf_size];
  	b2 = &block[2 * srv_sort_buf_size];
  
  	b0 = row_merge_read_rec(
  		&block[0], &buf[0], b0, dup->index,
  		file->fd, foffs0, &mrec0, offsets0,
  		crypt_block ? &crypt_block[0] : NULL,
  		space);
  
  	b1 = row_merge_read_rec(
  		&block[srv_sort_buf_size],
  		&buf[srv_sort_buf_size], b1, dup->index,
  		file->fd, foffs1, &mrec1, offsets1,
  		crypt_block ? &crypt_block[srv_sort_buf_size] : NULL,
  		space);
  
  	if (UNIV_UNLIKELY(!b0 && mrec0)
  	    || UNIV_UNLIKELY(!b1 && mrec1)) {
  
  		goto corrupt;
  	}
  
  	while (mrec0 && mrec1) {
  		int cmp = cmp_rec_rec_simple(
  			mrec0, mrec1, offsets0, offsets1,
  			dup->index, dup->table);
  		if (cmp < 0) {
  			ROW_MERGE_WRITE_GET_NEXT(0, dup->index, goto merged);
  		} else if (cmp) {
  			ROW_MERGE_WRITE_GET_NEXT(1, dup->index, goto merged);
  		} else {
  			mem_heap_free(heap);
  			DBUG_RETURN(DB_DUPLICATE_KEY);
  		}
  	}
  
  merged:
  	if (mrec0) {
  		/* append all mrec0 to output */
  		for (;;) {
  			ROW_MERGE_WRITE_GET_NEXT(0, dup->index, goto done0);
  		}
  	}
  done0:
  	if (mrec1) {
  		/* append all mrec1 to output */
  		for (;;) {
  			ROW_MERGE_WRITE_GET_NEXT(1, dup->index, goto done1);
  		}
  	}
  done1:
  
  	mem_heap_free(heap);
  
  	b2 = row_merge_write_eof(
  		&block[2 * srv_sort_buf_size],
  		b2, of->fd, &of->offset,
  		crypt_block ? &crypt_block[2 * srv_sort_buf_size] : NULL,
  		space);
  	DBUG_RETURN(b2 ? DB_SUCCESS : DB_CORRUPTION);
  }
  
  /** Copy a block of index entries.
  @param[in]	index	index being created
  @param[in]	file	input file
  @param[in,out]	block	3 buffers
  @param[in,out]	foffs0	input file offset
  @param[in,out]	of	output file
  @param[in,out]	stage	performance schema accounting object, used by
  ALTER TABLE. If not NULL stage->inc() will be called for each record
  processed.
  @param[in,out]	crypt_block	encryption buffer
  @param[in]	space	tablespace ID for encryption
  @return TRUE on success, FALSE on failure */
  static MY_ATTRIBUTE((warn_unused_result))
  ibool
  row_merge_blocks_copy(
  	const dict_index_t*	index,
  	const merge_file_t*	file,
  	row_merge_block_t*	block,
  	ulint*			foffs0,
  	merge_file_t*		of,
  	ut_stage_alter_t*	stage MY_ATTRIBUTE((unused)),
  	row_merge_block_t*	crypt_block,
  	ulint			space)
  {
  	mem_heap_t*	heap;	/*!< memory heap for offsets0, offsets1 */
  
  	mrec_buf_t*	buf;	/*!< buffer for handling
  				split mrec in block[] */
  	const byte*	b0;	/*!< pointer to block[0] */
  	byte*		b2;	/*!< pointer to block[2 * srv_sort_buf_size] */
  	const mrec_t*	mrec0;	/*!< merge rec, points to block[0] */
  	ulint*		offsets0;/* offsets of mrec0 */
  	ulint*		offsets1;/* dummy offsets */
  
  	DBUG_ENTER("row_merge_blocks_copy");
  	DBUG_LOG("ib_merge_sort",
  		 "fd=" << file->fd << ',' << foffs0
  		 << " to fd=" << of->fd << ',' << of->offset);
  
  	heap = row_merge_heap_create(index, &buf, &offsets0, &offsets1);
  
  	/* Write a record and read the next record.  Split the output
  	file in two halves, which can be merged on the following pass. */
  
  	if (!row_merge_read(file->fd, *foffs0, &block[0],
  			crypt_block ? &crypt_block[0] : NULL,
  			space)) {
  corrupt:
  		mem_heap_free(heap);
  		DBUG_RETURN(FALSE);
  	}
  
  	b0 = &block[0];
  
  	b2 = &block[2 * srv_sort_buf_size];
  
  	b0 = row_merge_read_rec(&block[0], &buf[0], b0, index,
  				file->fd, foffs0, &mrec0, offsets0,
  				crypt_block ? &crypt_block[0] : NULL,
  				space);
  
  	if (UNIV_UNLIKELY(!b0 && mrec0)) {
  
  		goto corrupt;
  	}
  
  	if (mrec0) {
  		/* append all mrec0 to output */
  		for (;;) {
  			ROW_MERGE_WRITE_GET_NEXT(0, index, goto done0);
  		}
  	}
  done0:
  
  	/* The file offset points to the beginning of the last page
  	that has been read.  Update it to point to the next block. */
  	(*foffs0)++;
  
  	mem_heap_free(heap);
  
  	DBUG_RETURN(row_merge_write_eof(
  			    &block[2 * srv_sort_buf_size],
  			    b2, of->fd, &of->offset,
  			    crypt_block
  			    ? &crypt_block[2 * srv_sort_buf_size]
  			    : NULL, space)
  		    != NULL);
  }
  
  /** Merge disk files.
  @param[in]	trx		transaction
  @param[in]	dup		descriptor of index being created
  @param[in,out]	file		file containing index entries
  @param[in,out]	block		3 buffers
  @param[in,out]	tmpfd		temporary file handle
  @param[in,out]	num_run		Number of runs that remain to be merged
  @param[in,out]	run_offset	Array that contains the first offset number
  for each merge run
  @param[in,out]	stage		performance schema accounting object, used by
  @param[in,out]	crypt_block	encryption buffer
  @param[in]	space		tablespace ID for encryption
  ALTER TABLE. If not NULL stage->inc() will be called for each record
  processed.
  @return DB_SUCCESS or error code */
  static
  dberr_t
  row_merge(
  	trx_t*			trx,
  	const row_merge_dup_t*	dup,
  	merge_file_t*		file,
  	row_merge_block_t*	block,
  	pfs_os_file_t*		tmpfd,
  	ulint*			num_run,
  	ulint*			run_offset,
  	ut_stage_alter_t*	stage,
  	row_merge_block_t*	crypt_block,
  	ulint			space)
  {
  	ulint		foffs0;	/*!< first input offset */
  	ulint		foffs1;	/*!< second input offset */
  	dberr_t		error;	/*!< error code */
  	merge_file_t	of;	/*!< output file */
  	const ulint	ihalf	= run_offset[*num_run / 2];
  				/*!< half the input file */
  	ulint		n_run	= 0;
  				/*!< num of runs generated from this merge */
  
  	UNIV_MEM_ASSERT_W(&block[0], 3 * srv_sort_buf_size);
  
  	if (crypt_block) {
  		UNIV_MEM_ASSERT_W(&crypt_block[0], 3 * srv_sort_buf_size);
  	}
  
  	ut_ad(ihalf < file->offset);
  
  	of.fd = *tmpfd;
  	of.offset = 0;
  	of.n_rec = 0;
  
  #ifdef POSIX_FADV_SEQUENTIAL
  	/* The input file will be read sequentially, starting from the
  	beginning and the middle.  In Linux, the POSIX_FADV_SEQUENTIAL
  	affects the entire file.  Each block will be read exactly once. */
  	posix_fadvise(file->fd, 0, 0,
  		      POSIX_FADV_SEQUENTIAL | POSIX_FADV_NOREUSE);
  #endif /* POSIX_FADV_SEQUENTIAL */
  
  	/* Merge blocks to the output file. */
  	foffs0 = 0;
  	foffs1 = ihalf;
  
  	UNIV_MEM_INVALID(run_offset, *num_run * sizeof *run_offset);
  
  	for (; foffs0 < ihalf && foffs1 < file->offset; foffs0++, foffs1++) {
  
  		if (trx_is_interrupted(trx)) {
  			return(DB_INTERRUPTED);
  		}
  
  		/* Remember the offset number for this run */
  		run_offset[n_run++] = of.offset;
  
  		error = row_merge_blocks(dup, file, block,
  					 &foffs0, &foffs1, &of, stage,
  					 crypt_block, space);
  
  		if (error != DB_SUCCESS) {
  			return(error);
  		}
  
  	}
  
  	/* Copy the last blocks, if there are any. */
  
  	while (foffs0 < ihalf) {
  
  		if (UNIV_UNLIKELY(trx_is_interrupted(trx))) {
  			return(DB_INTERRUPTED);
  		}
  
  		/* Remember the offset number for this run */
  		run_offset[n_run++] = of.offset;
  
  		if (!row_merge_blocks_copy(dup->index, file, block,
  					   &foffs0, &of, stage,
  					   crypt_block, space)) {
  			return(DB_CORRUPTION);
  		}
  	}
  
  	ut_ad(foffs0 == ihalf);
  
  	while (foffs1 < file->offset) {
  
  		if (trx_is_interrupted(trx)) {
  			return(DB_INTERRUPTED);
  		}
  
  		/* Remember the offset number for this run */
  		run_offset[n_run++] = of.offset;
  
  		if (!row_merge_blocks_copy(dup->index, file, block,
  					   &foffs1, &of, stage,
  					   crypt_block, space)) {
  			return(DB_CORRUPTION);
  		}
  	}
  
  	ut_ad(foffs1 == file->offset);
  
  	if (UNIV_UNLIKELY(of.n_rec != file->n_rec)) {
  		return(DB_CORRUPTION);
  	}
  
  	ut_ad(n_run <= *num_run);
  
  	*num_run = n_run;
  
  	/* Each run can contain one or more offsets. As merge goes on,
  	the number of runs (to merge) will reduce until we have one
  	single run. So the number of runs will always be smaller than
  	the number of offsets in file */
  	ut_ad((*num_run) <= file->offset);
  
  	/* The number of offsets in output file is always equal or
  	smaller than input file */
  	ut_ad(of.offset <= file->offset);
  
  	/* Swap file descriptors for the next pass. */
  	*tmpfd = file->fd;
  	*file = of;
  
  	UNIV_MEM_INVALID(&block[0], 3 * srv_sort_buf_size);
  
  	return(DB_SUCCESS);
  }
  
  /** Merge disk files.
  @param[in]	trx	transaction
  @param[in]	dup	descriptor of index being created
  @param[in,out]	file	file containing index entries
  @param[in,out]	block	3 buffers
  @param[in,out]	tmpfd	temporary file handle
  @param[in,out]	stage	performance schema accounting object, used by
  ALTER TABLE. If not NULL, stage->begin_phase_sort() will be called initially
  and then stage->inc() will be called for each record processed.
  @return DB_SUCCESS or error code */
  dberr_t
  row_merge_sort(
  	trx_t*			trx,
  	const row_merge_dup_t*	dup,
  	merge_file_t*		file,
  	row_merge_block_t*	block,
  	pfs_os_file_t*			tmpfd,
  	const bool		update_progress,
  					/*!< in: update progress
  					status variable or not */
  	const double 		pct_progress,
  					/*!< in: total progress percent
  					until now */
  	const double		pct_cost, /*!< in: current progress percent */
  	row_merge_block_t*	crypt_block, /*!< in: crypt buf or NULL */
  	ulint			space,	   /*!< in: space id */
  	ut_stage_alter_t* 	stage)
  {
  	const ulint	half	= file->offset / 2;
  	ulint		num_runs;
  	ulint*		run_offset;
  	dberr_t		error	= DB_SUCCESS;
  	ulint		merge_count = 0;
  	ulint		total_merge_sort_count;
  	double		curr_progress = 0;
  
  	DBUG_ENTER("row_merge_sort");
  
  	/* Record the number of merge runs we need to perform */
  	num_runs = file->offset;
  
  	if (stage != NULL) {
  		stage->begin_phase_sort(log2(num_runs));
  	}
  
  	/* Find the number N which 2^N is greater or equal than num_runs */
  	/* N is merge sort running count */
  	total_merge_sort_count = (ulint) ceil(my_log2f((float)num_runs));
  	if(total_merge_sort_count <= 0) {
  		total_merge_sort_count=1;
  	}
  
  	/* If num_runs are less than 1, nothing to merge */
  	if (num_runs <= 1) {
  		DBUG_RETURN(error);
  	}
  
  	/* "run_offset" records each run's first offset number */
  	run_offset = (ulint*) ut_malloc_nokey(file->offset * sizeof(ulint));
  
  	/* This tells row_merge() where to start for the first round
  	of merge. */
  	run_offset[half] = half;
  
  	/* The file should always contain at least one byte (the end
  	of file marker).  Thus, it must be at least one block. */
  	ut_ad(file->offset > 0);
  
  	/* These thd_progress* calls will crash on sol10-64 when innodb_plugin
  	is used. MDEV-9356: innodb.innodb_bug53290 fails (crashes) on
  	sol10-64 in buildbot.
  	*/
  #ifndef UNIV_SOLARIS
  	/* Progress report only for "normal" indexes. */
  	if (!(dup->index->type & DICT_FTS)) {
  		thd_progress_init(trx->mysql_thd, 1);
  	}
  #endif /* UNIV_SOLARIS */
  
  	if (global_system_variables.log_warnings > 2) {
  		sql_print_information("InnoDB: Online DDL : merge-sorting"
  				      " has estimated " ULINTPF " runs",
  				      num_runs);
  	}
  
  	/* Merge the runs until we have one big run */
  	do {
  		/* Report progress of merge sort to MySQL for
  		show processlist progress field */
  		/* Progress report only for "normal" indexes. */
  #ifndef UNIV_SOLARIS
  		if (!(dup->index->type & DICT_FTS)) {
  			thd_progress_report(trx->mysql_thd, file->offset - num_runs, file->offset);
  		}
  #endif /* UNIV_SOLARIS */
  
  		error = row_merge(trx, dup, file, block, tmpfd,
  				  &num_runs, run_offset, stage,
  				  crypt_block, space);
  
  		if(update_progress) {
  			merge_count++;
  			curr_progress = (merge_count >= total_merge_sort_count) ?
  				pct_cost :
  				((pct_cost * merge_count) / total_merge_sort_count);
  			/* presenting 10.12% as 1012 integer */;
  			onlineddl_pct_progress = (ulint) ((pct_progress + curr_progress) * 100);
  		}
  
  		if (error != DB_SUCCESS) {
  			break;
  		}
  
  		UNIV_MEM_ASSERT_RW(run_offset, num_runs * sizeof *run_offset);
  	} while (num_runs > 1);
  
  	ut_free(run_offset);
  
  	/* Progress report only for "normal" indexes. */
  #ifndef UNIV_SOLARIS
  	if (!(dup->index->type & DICT_FTS)) {
  		thd_progress_end(trx->mysql_thd);
  	}
  #endif /* UNIV_SOLARIS */
  
  	DBUG_RETURN(error);
  }
  
  /** Copy externally stored columns to the data tuple.
  @param[in]	mrec		record containing BLOB pointers,
  or NULL to use tuple instead
  @param[in]	offsets		offsets of mrec
  @param[in]	zip_size	compressed page size in bytes, or 0
  @param[in,out]	tuple		data tuple
  @param[in,out]	heap		memory heap */
  static
  void
  row_merge_copy_blobs(
  	const mrec_t*		mrec,
  	const ulint*		offsets,
  	const page_size_t&	page_size,
  	dtuple_t*		tuple,
  	mem_heap_t*		heap)
  {
  	ut_ad(mrec == NULL || rec_offs_any_extern(offsets));
  
  	for (ulint i = 0; i < dtuple_get_n_fields(tuple); i++) {
  		ulint		len;
  		const void*	data;
  		dfield_t*	field = dtuple_get_nth_field(tuple, i);
  		ulint		field_len;
  		const byte*	field_data;
  
  		if (!dfield_is_ext(field)) {
  			continue;
  		}
  
  		ut_ad(!dfield_is_null(field));
  
  		/* During the creation of a PRIMARY KEY, the table is
  		X-locked, and we skip copying records that have been
  		marked for deletion. Therefore, externally stored
  		columns cannot possibly be freed between the time the
  		BLOB pointers are read (row_merge_read_clustered_index())
  		and dereferenced (below). */
  		if (mrec == NULL) {
  			field_data
  				= static_cast<byte*>(dfield_get_data(field));
  			field_len = dfield_get_len(field);
  
  			ut_a(field_len >= BTR_EXTERN_FIELD_REF_SIZE);
  
  			ut_a(memcmp(field_data + field_len
  				     - BTR_EXTERN_FIELD_REF_SIZE,
  				     field_ref_zero,
  				     BTR_EXTERN_FIELD_REF_SIZE));
  
  			data = btr_copy_externally_stored_field(
  				&len, field_data, page_size, field_len, heap);
  		} else {
  			data = btr_rec_copy_externally_stored_field(
  				mrec, offsets, page_size, i, &len, heap);
  		}
  
  		/* Because we have locked the table, any records
  		written by incomplete transactions must have been
  		rolled back already. There must not be any incomplete
  		BLOB columns. */
  		ut_a(data);
  
  		dfield_set_data(field, data, len);
  	}
  }
  
  /** Convert a merge record to a typed data tuple. Note that externally
  stored fields are not copied to heap.
  @param[in,out]	index	index on the table
  @param[in]	mtuple	merge record
  @param[in]	heap	memory heap from which memory needed is allocated
  @return	index entry built. */
  static
  void
  row_merge_mtuple_to_dtuple(
  	dict_index_t*	index,
  	dtuple_t*	dtuple,
  	const mtuple_t* mtuple)
  {
  	ut_ad(!dict_index_is_ibuf(index));
  
  	memcpy(dtuple->fields, mtuple->fields,
  	       dtuple->n_fields * sizeof *mtuple->fields);
  }
  
  /** Insert sorted data tuples to the index.
  @param[in]	index		index to be inserted
  @param[in]	old_table	old table
  @param[in]	fd		file descriptor
  @param[in,out]	block		file buffer
  @param[in]	row_buf		row_buf the sorted data tuples,
  or NULL if fd, block will be used instead
  @param[in,out]	btr_bulk	btr bulk instance
  @param[in,out]	stage		performance schema accounting object, used by
  ALTER TABLE. If not NULL stage->begin_phase_insert() will be called initially
  and then stage->inc() will be called for each record that is processed.
  @return DB_SUCCESS or error number */
  static	MY_ATTRIBUTE((warn_unused_result))
  dberr_t
  row_merge_insert_index_tuples(
  	dict_index_t*		index,
  	const dict_table_t*	old_table,
  	const pfs_os_file_t&	fd,
  	row_merge_block_t*	block,
  	const row_merge_buf_t*	row_buf,
  	BtrBulk*		btr_bulk,
  	const ib_uint64_t	table_total_rows, /*!< in: total rows of old table */
  	const double		pct_progress,	/*!< in: total progress
  						percent until now */
  	const double		pct_cost, /*!< in: current progress percent
  					  */
  	row_merge_block_t*	crypt_block, /*!< in: crypt buf or NULL */
  	ulint			space,	   /*!< in: space id */
  	ut_stage_alter_t*	stage)
  {
  	const byte*		b;
  	mem_heap_t*		heap;
  	mem_heap_t*		tuple_heap;
  	dberr_t			error = DB_SUCCESS;
  	ulint			foffs = 0;
  	ulint*			offsets;
  	mrec_buf_t*		buf;
  	ulint			n_rows = 0;
  	dtuple_t*		dtuple;
  	ib_uint64_t		inserted_rows = 0;
  	double			curr_progress = 0;
  	dict_index_t*		old_index = NULL;
  	const mrec_t*		mrec  = NULL;
  	ulint			n_ext = 0;
  	mtr_t			mtr;
  
  
  	DBUG_ENTER("row_merge_insert_index_tuples");
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad(!(index->type & DICT_FTS));
  	ut_ad(!dict_index_is_spatial(index));
  
  	if (stage != NULL) {
  		stage->begin_phase_insert();
  	}
  
  	tuple_heap = mem_heap_create(1000);
  
  	{
  		ulint i	= 1 + REC_OFFS_HEADER_SIZE
  			+ dict_index_get_n_fields(index);
  		heap = mem_heap_create(sizeof *buf + i * sizeof *offsets);
  		offsets = static_cast<ulint*>(
  			mem_heap_alloc(heap, i * sizeof *offsets));
  		offsets[0] = i;
  		offsets[1] = dict_index_get_n_fields(index);
  	}
  
  	if (row_buf != NULL) {
  		ut_ad(fd == OS_FILE_CLOSED);
  		ut_ad(block == NULL);
  		DBUG_EXECUTE_IF("row_merge_read_failure",
  				error = DB_CORRUPTION;
  				goto err_exit;);
  		buf = NULL;
  		b = NULL;
  		dtuple = dtuple_create(
  			heap, dict_index_get_n_fields(index));
  		dtuple_set_n_fields_cmp(
  			dtuple, dict_index_get_n_unique_in_tree(index));
  	} else {
  		b = block;
  		dtuple = NULL;
  
  		if (!row_merge_read(fd, foffs, block, crypt_block, space)) {
  			error = DB_CORRUPTION;
  			goto err_exit;
  		} else {
  			buf = static_cast<mrec_buf_t*>(
  				mem_heap_alloc(heap, sizeof *buf));
  		}
  	}
  
  	for (;;) {
  
  		if (stage != NULL) {
  			stage->inc();
  		}
  
  		if (row_buf != NULL) {
  			if (n_rows >= row_buf->n_tuples) {
  				break;
  			}
  
  			/* Convert merge tuple record from
  			row buffer to data tuple record */
  			row_merge_mtuple_to_dtuple(
  				index, dtuple, &row_buf->tuples[n_rows]);
  
  			n_ext = dtuple_get_n_ext(dtuple);
  			n_rows++;
  			/* BLOB pointers must be copied from dtuple */
  			mrec = NULL;
  		} else {
  			b = row_merge_read_rec(block, buf, b, index,
  					       fd, &foffs, &mrec, offsets,
  					       crypt_block,
  					       space);
  
  			if (UNIV_UNLIKELY(!b)) {
  				/* End of list, or I/O error */
  				if (mrec) {
  					error = DB_CORRUPTION;
  				}
  				break;
  			}
  
  			dtuple = row_rec_to_index_entry_low(
  				mrec, index, offsets, &n_ext, tuple_heap);
  		}
  
  		old_index	= dict_table_get_first_index(old_table);
  
  		if (dict_index_is_clust(index)
  		    && dict_index_is_online_ddl(old_index)) {
  			error = row_log_table_get_error(old_index);
  			if (error != DB_SUCCESS) {
  				break;
  			}
  		}
  
  		if (!n_ext) {
  			/* There are no externally stored columns. */
  		} else {
  			ut_ad(dict_index_is_clust(index));
  			/* Off-page columns can be fetched safely
  			when concurrent modifications to the table
  			are disabled. (Purge can process delete-marked
  			records, but row_merge_read_clustered_index()
  			would have skipped them.)
  
  			When concurrent modifications are enabled,
  			row_merge_read_clustered_index() will
  			only see rows from transactions that were
  			committed before the ALTER TABLE started
  			(REPEATABLE READ).
  
  			Any modifications after the
  			row_merge_read_clustered_index() scan
  			will go through row_log_table_apply().
  			Any modifications to off-page columns
  			will be tracked by
  			row_log_table_blob_alloc() and
  			row_log_table_blob_free(). */
  			row_merge_copy_blobs(
  				mrec, offsets,
  				dict_table_page_size(old_table),
  				dtuple, tuple_heap);
  		}
  
  #ifdef UNIV_DEBUG
  		static const latch_level_t latches[] = {
  			SYNC_INDEX_TREE,	/* index->lock */
  			SYNC_LEVEL_VARYING	/* btr_bulk->m_page_bulks */
  		};
  #endif /* UNIV_DEBUG */
  
  		ut_ad(dtuple_validate(dtuple));
  		ut_ad(!sync_check_iterate(sync_allowed_latches(latches,
  							       latches + 2)));
  		error = btr_bulk->insert(dtuple);
  
  		if (error != DB_SUCCESS) {
  			goto err_exit;
  		}
  
  		mem_heap_empty(tuple_heap);
  
  		/* Increment innodb_onlineddl_pct_progress status variable */
  		inserted_rows++;
  		if(inserted_rows % 1000 == 0) {
  			/* Update progress for each 1000 rows */
  			curr_progress = (inserted_rows >= table_total_rows ||
  				table_total_rows <= 0) ?
  				pct_cost :
  				((pct_cost * inserted_rows) / table_total_rows);
  
  			/* presenting 10.12% as 1012 integer */;
  			onlineddl_pct_progress = (ulint) ((pct_progress + curr_progress) * 100);
  		}
  	}
  
  err_exit:
  	mem_heap_free(tuple_heap);
  	mem_heap_free(heap);
  
  	DBUG_RETURN(error);
  }
  
  /*********************************************************************//**
  Sets an exclusive lock on a table, for the duration of creating indexes.
  @return error code or DB_SUCCESS */
  dberr_t
  row_merge_lock_table(
  /*=================*/
  	trx_t*		trx,		/*!< in/out: transaction */
  	dict_table_t*	table,		/*!< in: table to lock */
  	enum lock_mode	mode)		/*!< in: LOCK_X or LOCK_S */
  {
  	ut_ad(!srv_read_only_mode);
  	ut_ad(mode == LOCK_X || mode == LOCK_S);
  
  	trx->op_info = "setting table lock for creating or dropping index";
  	trx->ddl = true;
  
  	return(lock_table_for_trx(table, trx, mode));
  }
  
  /*********************************************************************//**
  Drop an index that was created before an error occurred.
  The data dictionary must have been locked exclusively by the caller,
  because the transaction will not be committed. */
  static
  void
  row_merge_drop_index_dict(
  /*======================*/
  	trx_t*		trx,	/*!< in/out: dictionary transaction */
  	index_id_t	index_id)/*!< in: index identifier */
  {
  	static const char sql[] =
  		"PROCEDURE DROP_INDEX_PROC () IS\n"
  		"BEGIN\n"
  		"DELETE FROM SYS_FIELDS WHERE INDEX_ID=:indexid;\n"
  		"DELETE FROM SYS_INDEXES WHERE ID=:indexid;\n"
  		"END;\n";
  	dberr_t		error;
  	pars_info_t*	info;
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad(mutex_own(&dict_sys->mutex));
  	ut_ad(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  	ut_ad(rw_lock_own(dict_operation_lock, RW_LOCK_X));
  
  	info = pars_info_create();
  	pars_info_add_ull_literal(info, "indexid", index_id);
  	trx->op_info = "dropping index from dictionary";
  	error = que_eval_sql(info, sql, FALSE, trx);
  
  	if (error != DB_SUCCESS) {
  		/* Even though we ensure that DDL transactions are WAIT
  		and DEADLOCK free, we could encounter other errors e.g.,
  		DB_TOO_MANY_CONCURRENT_TRXS. */
  		trx->error_state = DB_SUCCESS;
  
  		ib::error() << "row_merge_drop_index_dict failed with error "
  			<< error;
  	}
  
  	trx->op_info = "";
  }
  
  /*********************************************************************//**
  Drop indexes that were created before an error occurred.
  The data dictionary must have been locked exclusively by the caller,
  because the transaction will not be committed. */
  void
  row_merge_drop_indexes_dict(
  /*========================*/
  	trx_t*		trx,	/*!< in/out: dictionary transaction */
  	table_id_t	table_id)/*!< in: table identifier */
  {
  	static const char sql[] =
  		"PROCEDURE DROP_INDEXES_PROC () IS\n"
  		"ixid CHAR;\n"
  		"found INT;\n"
  
  		"DECLARE CURSOR index_cur IS\n"
  		" SELECT ID FROM SYS_INDEXES\n"
  		" WHERE TABLE_ID=:tableid AND\n"
  		" SUBSTR(NAME,0,1)='" TEMP_INDEX_PREFIX_STR "'\n"
  		"FOR UPDATE;\n"
  
  		"BEGIN\n"
  		"found := 1;\n"
  		"OPEN index_cur;\n"
  		"WHILE found = 1 LOOP\n"
  		"  FETCH index_cur INTO ixid;\n"
  		"  IF (SQL % NOTFOUND) THEN\n"
  		"    found := 0;\n"
  		"  ELSE\n"
  		"    DELETE FROM SYS_FIELDS WHERE INDEX_ID=ixid;\n"
  		"    DELETE FROM SYS_INDEXES WHERE CURRENT OF index_cur;\n"
  		"  END IF;\n"
  		"END LOOP;\n"
  		"CLOSE index_cur;\n"
  
  		"END;\n";
  	dberr_t		error;
  	pars_info_t*	info;
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad(mutex_own(&dict_sys->mutex));
  	ut_ad(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  	ut_ad(rw_lock_own(dict_operation_lock, RW_LOCK_X));
  
  	/* It is possible that table->n_ref_count > 1 when
  	locked=TRUE. In this case, all code that should have an open
  	handle to the table be waiting for the next statement to execute,
  	or waiting for a meta-data lock.
  
  	A concurrent purge will be prevented by dict_operation_lock. */
  
  	info = pars_info_create();
  	pars_info_add_ull_literal(info, "tableid", table_id);
  	trx->op_info = "dropping indexes";
  	error = que_eval_sql(info, sql, FALSE, trx);
  
  	switch (error) {
  	case DB_SUCCESS:
  		break;
  	default:
  		/* Even though we ensure that DDL transactions are WAIT
  		and DEADLOCK free, we could encounter other errors e.g.,
  		DB_TOO_MANY_CONCURRENT_TRXS. */
  		ib::error() << "row_merge_drop_indexes_dict failed with error "
  			<< error;
  		/* fall through */
  	case DB_TOO_MANY_CONCURRENT_TRXS:
  		trx->error_state = DB_SUCCESS;
  	}
  
  	trx->op_info = "";
  }
  
  /*********************************************************************//**
  Drop indexes that were created before an error occurred.
  The data dictionary must have been locked exclusively by the caller,
  because the transaction will not be committed. */
  void
  row_merge_drop_indexes(
  /*===================*/
  	trx_t*		trx,	/*!< in/out: dictionary transaction */
  	dict_table_t*	table,	/*!< in/out: table containing the indexes */
  	ibool		locked)	/*!< in: TRUE=table locked,
  				FALSE=may need to do a lazy drop */
  {
  	dict_index_t*	index;
  	dict_index_t*	next_index;
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad(mutex_own(&dict_sys->mutex));
  	ut_ad(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  	ut_ad(rw_lock_own(dict_operation_lock, RW_LOCK_X));
  
  	index = dict_table_get_first_index(table);
  	ut_ad(dict_index_is_clust(index));
  	ut_ad(dict_index_get_online_status(index) == ONLINE_INDEX_COMPLETE);
  
  	/* the caller should have an open handle to the table */
  	ut_ad(table->get_ref_count() >= 1);
  
  	/* It is possible that table->n_ref_count > 1 when
  	locked=TRUE. In this case, all code that should have an open
  	handle to the table be waiting for the next statement to execute,
  	or waiting for a meta-data lock.
  
  	A concurrent purge will be prevented by dict_operation_lock. */
  
  	if (!locked && (table->get_ref_count() > 1
  			|| UT_LIST_GET_FIRST(table->locks))) {
  		/* We will have to drop the indexes later, when the
  		table is guaranteed to be no longer in use.  Mark the
  		indexes as incomplete and corrupted, so that other
  		threads will stop using them.  Let dict_table_close()
  		or crash recovery or the next invocation of
  		prepare_inplace_alter_table() take care of dropping
  		the indexes. */
  
  		while ((index = dict_table_get_next_index(index)) != NULL) {
  			ut_ad(!dict_index_is_clust(index));
  
  			switch (dict_index_get_online_status(index)) {
  			case ONLINE_INDEX_ABORTED_DROPPED:
  				continue;
  			case ONLINE_INDEX_COMPLETE:
  				if (index->is_committed()) {
  					/* Do nothing to already
  					published indexes. */
  				} else if (index->type & DICT_FTS) {
  					/* Drop a completed FULLTEXT
  					index, due to a timeout during
  					MDL upgrade for
  					commit_inplace_alter_table().
  					Because only concurrent reads
  					are allowed (and they are not
  					seeing this index yet) we
  					are safe to drop the index. */
  					dict_index_t* prev = UT_LIST_GET_PREV(
  						indexes, index);
  					/* At least there should be
  					the clustered index before
  					this one. */
  					ut_ad(prev);
  					ut_a(table->fts);
  					fts_drop_index(table, index, trx);
  					/* Since
  					INNOBASE_SHARE::idx_trans_tbl
  					is shared between all open
  					ha_innobase handles to this
  					table, no thread should be
  					accessing this dict_index_t
  					object. Also, we should be
  					holding LOCK=SHARED MDL on the
  					table even after the MDL
  					upgrade timeout. */
  
  					/* We can remove a DICT_FTS
  					index from the cache, because
  					we do not allow ADD FULLTEXT INDEX
  					with LOCK=NONE. If we allowed that,
  					we should exclude FTS entries from
  					prebuilt->ins_node->entry_list
  					in ins_node_create_entry_list(). */
  					dict_index_remove_from_cache(
  						table, index);
  					index = prev;
  				} else {
  					rw_lock_x_lock(
  						dict_index_get_lock(index));
  					dict_index_set_online_status(
  						index, ONLINE_INDEX_ABORTED);
  					index->type |= DICT_CORRUPT;
  					table->drop_aborted = TRUE;
  					goto drop_aborted;
  				}
  				continue;
  			case ONLINE_INDEX_CREATION:
  				rw_lock_x_lock(dict_index_get_lock(index));
  				ut_ad(!index->is_committed());
  				row_log_abort_sec(index);
  			drop_aborted:
  				rw_lock_x_unlock(dict_index_get_lock(index));
  
  				DEBUG_SYNC_C("merge_drop_index_after_abort");
  				/* covered by dict_sys->mutex */
  				MONITOR_INC(MONITOR_BACKGROUND_DROP_INDEX);
  				/* fall through */
  			case ONLINE_INDEX_ABORTED:
  				/* Drop the index tree from the
  				data dictionary and free it from
  				the tablespace, but keep the object
  				in the data dictionary cache. */
  				row_merge_drop_index_dict(trx, index->id);
  				rw_lock_x_lock(dict_index_get_lock(index));
  				dict_index_set_online_status(
  					index, ONLINE_INDEX_ABORTED_DROPPED);
  				rw_lock_x_unlock(dict_index_get_lock(index));
  				table->drop_aborted = TRUE;
  				continue;
  			}
  			ut_error;
  		}
  
  		return;
  	}
  
  	row_merge_drop_indexes_dict(trx, table->id);
  
  	/* Invalidate all row_prebuilt_t::ins_graph that are referring
  	to this table. That is, force row_get_prebuilt_insert_row() to
  	rebuild prebuilt->ins_node->entry_list). */
  	ut_ad(table->def_trx_id <= trx->id);
  	table->def_trx_id = trx->id;
  
  	next_index = dict_table_get_next_index(index);
  
  	while ((index = next_index) != NULL) {
  		/* read the next pointer before freeing the index */
  		next_index = dict_table_get_next_index(index);
  
  		ut_ad(!dict_index_is_clust(index));
  
  		if (!index->is_committed()) {
  			/* If it is FTS index, drop from table->fts
  			and also drop its auxiliary tables */
  			if (index->type & DICT_FTS) {
  				ut_a(table->fts);
  				fts_drop_index(table, index, trx);
  			}
  
  			switch (dict_index_get_online_status(index)) {
  			case ONLINE_INDEX_CREATION:
  				/* This state should only be possible
  				when prepare_inplace_alter_table() fails
  				after invoking row_merge_create_index().
  				In inplace_alter_table(),
  				row_merge_build_indexes()
  				should never leave the index in this state.
  				It would invoke row_log_abort_sec() on
  				failure. */
  			case ONLINE_INDEX_COMPLETE:
  				/* In these cases, we are able to drop
  				the index straight. The DROP INDEX was
  				never deferred. */
  				break;
  			case ONLINE_INDEX_ABORTED:
  			case ONLINE_INDEX_ABORTED_DROPPED:
  				/* covered by dict_sys->mutex */
  				MONITOR_DEC(MONITOR_BACKGROUND_DROP_INDEX);
  			}
  
  			dict_index_remove_from_cache(table, index);
  		}
  	}
  
  	table->drop_aborted = FALSE;
  	ut_d(dict_table_check_for_dup_indexes(table, CHECK_ALL_COMPLETE));
  }
  
  /*********************************************************************//**
  Drop all partially created indexes during crash recovery. */
  void
  row_merge_drop_temp_indexes(void)
  /*=============================*/
  {
  	static const char sql[] =
  		"PROCEDURE DROP_TEMP_INDEXES_PROC () IS\n"
  		"ixid CHAR;\n"
  		"found INT;\n"
  
  		"DECLARE CURSOR index_cur IS\n"
  		" SELECT ID FROM SYS_INDEXES\n"
  		" WHERE SUBSTR(NAME,0,1)='" TEMP_INDEX_PREFIX_STR "'\n"
  		"FOR UPDATE;\n"
  
  		"BEGIN\n"
  		"found := 1;\n"
  		"OPEN index_cur;\n"
  		"WHILE found = 1 LOOP\n"
  		"  FETCH index_cur INTO ixid;\n"
  		"  IF (SQL % NOTFOUND) THEN\n"
  		"    found := 0;\n"
  		"  ELSE\n"
  		"    DELETE FROM SYS_FIELDS WHERE INDEX_ID=ixid;\n"
  		"    DELETE FROM SYS_INDEXES WHERE CURRENT OF index_cur;\n"
  		"  END IF;\n"
  		"END LOOP;\n"
  		"CLOSE index_cur;\n"
  		"END;\n";
  	trx_t*	trx;
  	dberr_t	error;
  
  	/* Load the table definitions that contain partially defined
  	indexes, so that the data dictionary information can be checked
  	when accessing the tablename.ibd files. */
  	trx = trx_create();
  	trx->op_info = "dropping partially created indexes";
  	row_mysql_lock_data_dictionary(trx);
  	/* Ensure that this transaction will be rolled back and locks
  	will be released, if the server gets killed before the commit
  	gets written to the redo log. */
  	trx_set_dict_operation(trx, TRX_DICT_OP_INDEX);
  
  	trx->op_info = "dropping indexes";
  	error = que_eval_sql(NULL, sql, FALSE, trx);
  
  	if (error != DB_SUCCESS) {
  		/* Even though we ensure that DDL transactions are WAIT
  		and DEADLOCK free, we could encounter other errors e.g.,
  		DB_TOO_MANY_CONCURRENT_TRXS. */
  		trx->error_state = DB_SUCCESS;
  
  		ib::error() << "row_merge_drop_temp_indexes failed with error"
  			<< error;
  	}
  
  	trx_commit_for_mysql(trx);
  	row_mysql_unlock_data_dictionary(trx);
  	trx_free(trx);
  }
  
  
  /** Create temporary merge files in the given paramater path, and if
  UNIV_PFS_IO defined, register the file descriptor with Performance Schema.
  @param[in]	path	location for creating temporary merge files, or NULL
  @return File descriptor */
  pfs_os_file_t
  row_merge_file_create_low(
  	const char*	path)
  {
  	pfs_os_file_t	fd;
  #ifdef UNIV_PFS_IO
  	/* This temp file open does not go through normal
  	file APIs, add instrumentation to register with
  	performance schema */
  	struct PSI_file_locker*	locker = NULL;
  	PSI_file_locker_state	state;
  
  	register_pfs_file_open_begin(
  		&state, locker, innodb_temp_file_key,
  		PSI_FILE_CREATE,
  		"Innodb Merge Temp File", 
  		__FILE__, __LINE__);
  	
  #endif
  	fd = innobase_mysql_tmpfile(path);
  #ifdef UNIV_PFS_IO
  	register_pfs_file_open_end(locker, fd, 
  		(fd == OS_FILE_CLOSED)?NULL:&fd);
  #endif
  
  	if (fd == OS_FILE_CLOSED) {
  		ib::error() << "Cannot create temporary merge file";
  	}
  	return(fd);
  }
  
  
  /** Create a merge file in the given location.
  @param[out]	merge_file	merge file structure
  @param[in]	path		location for creating temporary file, or NULL
  @return file descriptor, or OS_FILE_CLOSED on error */
  pfs_os_file_t
  row_merge_file_create(
  	merge_file_t*	merge_file,
  	const char*	path)
  {
  	merge_file->fd = row_merge_file_create_low(path);
  	merge_file->offset = 0;
  	merge_file->n_rec = 0;
  
  	if (merge_file->fd != OS_FILE_CLOSED) {
  		if (srv_disable_sort_file_cache) {
  			os_file_set_nocache(merge_file->fd,
  				"row0merge.cc", "sort");
  		}
  	}
  	return(merge_file->fd);
  }
  
  /*********************************************************************//**
  Destroy a merge file. And de-register the file from Performance Schema
  if UNIV_PFS_IO is defined. */
  void
  row_merge_file_destroy_low(
  /*=======================*/
  	const pfs_os_file_t& fd)	/*!< in: merge file descriptor */
  {
  	if (fd != OS_FILE_CLOSED) {
  		os_file_close(fd);
  	}
  }
  /*********************************************************************//**
  Destroy a merge file. */
  void
  row_merge_file_destroy(
  /*===================*/
  	merge_file_t*	merge_file)	/*!< in/out: merge file structure */
  {
  	ut_ad(!srv_read_only_mode);
  
  	if (merge_file->fd != OS_FILE_CLOSED) {
  		row_merge_file_destroy_low(merge_file->fd);
  		merge_file->fd = OS_FILE_CLOSED;
  	}
  }
  
  /*********************************************************************//**
  Rename an index in the dictionary that was created. The data
  dictionary must have been locked exclusively by the caller, because
  the transaction will not be committed.
  @return DB_SUCCESS if all OK */
  dberr_t
  row_merge_rename_index_to_add(
  /*==========================*/
  	trx_t*		trx,		/*!< in/out: transaction */
  	table_id_t	table_id,	/*!< in: table identifier */
  	index_id_t	index_id)	/*!< in: index identifier */
  {
  	dberr_t		err = DB_SUCCESS;
  	pars_info_t*	info = pars_info_create();
  
  	/* We use the private SQL parser of Innobase to generate the
  	query graphs needed in renaming indexes. */
  
  	static const char rename_index[] =
  		"PROCEDURE RENAME_INDEX_PROC () IS\n"
  		"BEGIN\n"
  		"UPDATE SYS_INDEXES SET NAME=SUBSTR(NAME,1,LENGTH(NAME)-1)\n"
  		"WHERE TABLE_ID = :tableid AND ID = :indexid;\n"
  		"END;\n";
  
  	ut_ad(trx);
  	ut_a(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  
  	trx->op_info = "renaming index to add";
  
  	pars_info_add_ull_literal(info, "tableid", table_id);
  	pars_info_add_ull_literal(info, "indexid", index_id);
  
  	err = que_eval_sql(info, rename_index, FALSE, trx);
  
  	if (err != DB_SUCCESS) {
  		/* Even though we ensure that DDL transactions are WAIT
  		and DEADLOCK free, we could encounter other errors e.g.,
  		DB_TOO_MANY_CONCURRENT_TRXS. */
  		trx->error_state = DB_SUCCESS;
  
  		ib::error() << "row_merge_rename_index_to_add failed with"
  			" error " << err;
  	}
  
  	trx->op_info = "";
  
  	return(err);
  }
  
  /*********************************************************************//**
  Rename an index in the dictionary that is to be dropped. The data
  dictionary must have been locked exclusively by the caller, because
  the transaction will not be committed.
  @return DB_SUCCESS if all OK */
  dberr_t
  row_merge_rename_index_to_drop(
  /*===========================*/
  	trx_t*		trx,		/*!< in/out: transaction */
  	table_id_t	table_id,	/*!< in: table identifier */
  	index_id_t	index_id)	/*!< in: index identifier */
  {
  	dberr_t		err;
  	pars_info_t*	info = pars_info_create();
  
  	ut_ad(!srv_read_only_mode);
  
  	/* We use the private SQL parser of Innobase to generate the
  	query graphs needed in renaming indexes. */
  
  	static const char rename_index[] =
  		"PROCEDURE RENAME_INDEX_PROC () IS\n"
  		"BEGIN\n"
  		"UPDATE SYS_INDEXES SET NAME=CONCAT('"
  		TEMP_INDEX_PREFIX_STR "',NAME)\n"
  		"WHERE TABLE_ID = :tableid AND ID = :indexid;\n"
  		"END;\n";
  
  	ut_ad(trx);
  	ut_a(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  
  	trx->op_info = "renaming index to drop";
  
  	pars_info_add_ull_literal(info, "tableid", table_id);
  	pars_info_add_ull_literal(info, "indexid", index_id);
  
  	err = que_eval_sql(info, rename_index, FALSE, trx);
  
  	if (err != DB_SUCCESS) {
  		/* Even though we ensure that DDL transactions are WAIT
  		and DEADLOCK free, we could encounter other errors e.g.,
  		DB_TOO_MANY_CONCURRENT_TRXS. */
  		trx->error_state = DB_SUCCESS;
  
  		ib::error() << "row_merge_rename_index_to_drop failed with"
  			" error " << err;
  	}
  
  	trx->op_info = "";
  
  	return(err);
  }
  
  /*********************************************************************//**
  Provide a new pathname for a table that is being renamed if it belongs to
  a file-per-table tablespace.  The caller is responsible for freeing the
  memory allocated for the return value.
  @return new pathname of tablespace file, or NULL if space = 0 */
  char*
  row_make_new_pathname(
  /*==================*/
  	dict_table_t*	table,		/*!< in: table to be renamed */
  	const char*	new_name)	/*!< in: new name */
  {
  	ut_ad(!is_system_tablespace(table->space->id));
  	return os_file_make_new_pathname(table->space->chain.start->name,
  					 new_name);
  }
  
  /*********************************************************************//**
  Rename the tables in the data dictionary.  The data dictionary must
  have been locked exclusively by the caller, because the transaction
  will not be committed.
  @return error code or DB_SUCCESS */
  dberr_t
  row_merge_rename_tables_dict(
  /*=========================*/
  	dict_table_t*	old_table,	/*!< in/out: old table, renamed to
  					tmp_name */
  	dict_table_t*	new_table,	/*!< in/out: new table, renamed to
  					old_table->name */
  	const char*	tmp_name,	/*!< in: new name for old_table */
  	trx_t*		trx)		/*!< in/out: dictionary transaction */
  {
  	dberr_t		err	= DB_ERROR;
  	pars_info_t*	info;
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad(old_table != new_table);
  	ut_ad(mutex_own(&dict_sys->mutex));
  	ut_a(trx->dict_operation_lock_mode == RW_X_LATCH);
  	ut_ad(trx_get_dict_operation(trx) == TRX_DICT_OP_TABLE
  	      || trx_get_dict_operation(trx) == TRX_DICT_OP_INDEX);
  
  	trx->op_info = "renaming tables";
  
  	/* We use the private SQL parser of Innobase to generate the query
  	graphs needed in updating the dictionary data in system tables. */
  
  	info = pars_info_create();
  
  	pars_info_add_str_literal(info, "new_name", new_table->name.m_name);
  	pars_info_add_str_literal(info, "old_name", old_table->name.m_name);
  	pars_info_add_str_literal(info, "tmp_name", tmp_name);
  
  	err = que_eval_sql(info,
  			   "PROCEDURE RENAME_TABLES () IS\n"
  			   "BEGIN\n"
  			   "UPDATE SYS_TABLES SET NAME = :tmp_name\n"
  			   " WHERE NAME = :old_name;\n"
  			   "UPDATE SYS_TABLES SET NAME = :old_name\n"
  			   " WHERE NAME = :new_name;\n"
  			   "END;\n", FALSE, trx);
  
  	/* Update SYS_TABLESPACES and SYS_DATAFILES if the old table being
  	renamed is a single-table tablespace, which must be implicitly
  	renamed along with the table. */
  	if (err == DB_SUCCESS
  	    && old_table->space_id) {
  		/* Make pathname to update SYS_DATAFILES. */
  		char* tmp_path = row_make_new_pathname(old_table, tmp_name);
  
  		info = pars_info_create();
  
  		pars_info_add_str_literal(info, "tmp_name", tmp_name);
  		pars_info_add_str_literal(info, "tmp_path", tmp_path);
  		pars_info_add_int4_literal(info, "old_space",
  					   old_table->space_id);
  
  		err = que_eval_sql(info,
  				   "PROCEDURE RENAME_OLD_SPACE () IS\n"
  				   "BEGIN\n"
  				   "UPDATE SYS_TABLESPACES"
  				   " SET NAME = :tmp_name\n"
  				   " WHERE SPACE = :old_space;\n"
  				   "UPDATE SYS_DATAFILES"
  				   " SET PATH = :tmp_path\n"
  				   " WHERE SPACE = :old_space;\n"
  				   "END;\n", FALSE, trx);
  
  		ut_free(tmp_path);
  	}
  
  	/* Update SYS_TABLESPACES and SYS_DATAFILES if the new table being
  	renamed is a single-table tablespace, which must be implicitly
  	renamed along with the table. */
  	if (err == DB_SUCCESS
  	    && dict_table_is_file_per_table(new_table)) {
  		/* Make pathname to update SYS_DATAFILES. */
  		char* old_path = row_make_new_pathname(
  			new_table, old_table->name.m_name);
  
  		info = pars_info_create();
  
  		pars_info_add_str_literal(info, "old_name",
  					  old_table->name.m_name);
  		pars_info_add_str_literal(info, "old_path", old_path);
  		pars_info_add_int4_literal(info, "new_space",
  					   new_table->space_id);
  
  		err = que_eval_sql(info,
  				   "PROCEDURE RENAME_NEW_SPACE () IS\n"
  				   "BEGIN\n"
  				   "UPDATE SYS_TABLESPACES"
  				   " SET NAME = :old_name\n"
  				   " WHERE SPACE = :new_space;\n"
  				   "UPDATE SYS_DATAFILES"
  				   " SET PATH = :old_path\n"
  				   " WHERE SPACE = :new_space;\n"
  				   "END;\n", FALSE, trx);
  
  		ut_free(old_path);
  	}
  
  	if (err == DB_SUCCESS && (new_table->flags2 & DICT_TF2_DISCARDED)) {
  		err = row_import_update_discarded_flag(
  			trx, new_table->id, true);
  	}
  
  	trx->op_info = "";
  
  	return(err);
  }
  
  /** Create the index and load in to the dictionary.
  @param[in,out]	table		the index is on this table
  @param[in]	index_def	the index definition
  @param[in]	add_v		new virtual columns added along with add
  				index call
  @return index, or NULL on error */
  dict_index_t*
  row_merge_create_index(
  	dict_table_t*		table,
  	const index_def_t*	index_def,
  	const dict_add_v_col_t*	add_v)
  {
  	dict_index_t*	index;
  	ulint		n_fields = index_def->n_fields;
  	ulint		i;
  
  	DBUG_ENTER("row_merge_create_index");
  
  	ut_ad(!srv_read_only_mode);
  
  	/* Create the index prototype, using the passed in def, this is not
  	a persistent operation. We pass 0 as the space id, and determine at
  	a lower level the space id where to store the table. */
  
  	index = dict_mem_index_create(table, index_def->name,
  				      index_def->ind_type, n_fields);
  	index->set_committed(index_def->rebuild);
  
  	for (i = 0; i < n_fields; i++) {
  		const char*	name;
  		index_field_t*	ifield = &index_def->fields[i];
  
  		if (ifield->is_v_col) {
  			if (ifield->col_no >= table->n_v_def) {
  				ut_ad(ifield->col_no < table->n_v_def
  				      + add_v->n_v_col);
  				ut_ad(ifield->col_no >= table->n_v_def);
  				name = add_v->v_col_name[
  					ifield->col_no - table->n_v_def];
  				index->has_new_v_col = true;
  			} else {
  				name = dict_table_get_v_col_name(
  					table, ifield->col_no);
  			}
  		} else {
  			name = dict_table_get_col_name(table, ifield->col_no);
  		}
  
  		dict_mem_index_add_field(index, name, ifield->prefix_len);
  	}
  
  	DBUG_RETURN(index);
  }
  
  /*********************************************************************//**
  Check if a transaction can use an index. */
  bool
  row_merge_is_index_usable(
  /*======================*/
  	const trx_t*		trx,	/*!< in: transaction */
  	const dict_index_t*	index)	/*!< in: index to check */
  {
  	if (!index->is_primary()
  	    && dict_index_is_online_ddl(index)) {
  		/* Indexes that are being created are not useable. */
  		return(false);
  	}
  
  	return(!index->is_corrupted()
  	       && (index->table->is_temporary()
  		   || index->trx_id == 0
  		   || !trx->read_view.is_open()
  		   || trx->read_view.changes_visible(
  			   index->trx_id,
  			   index->table->name)));
  }
  
  /*********************************************************************//**
  Drop a table. The caller must have ensured that the background stats
  thread is not processing the table. This can be done by calling
  dict_stats_wait_bg_to_stop_using_table() after locking the dictionary and
  before calling this function.
  @return DB_SUCCESS or error code */
  dberr_t
  row_merge_drop_table(
  /*=================*/
  	trx_t*		trx,		/*!< in: transaction */
  	dict_table_t*	table)		/*!< in: table to drop */
  {
  	ut_ad(!srv_read_only_mode);
  
  	/* There must be no open transactions on the table. */
  	ut_a(table->get_ref_count() == 0);
  
  	return(row_drop_table_for_mysql(table->name.m_name,
  			trx, false, false, false));
  }
  
  /** Write an MLOG_INDEX_LOAD record to indicate in the redo-log
  that redo-logging of individual index pages was disabled, and
  the flushing of such pages to the data files was completed.
  @param[in]	index	an index tree on which redo logging was disabled */
  static
  void
  row_merge_write_redo(
  	const dict_index_t*	index)
  {
  	mtr_t	mtr;
  	byte*	log_ptr;
  
  	ut_ad(!index->table->is_temporary());
  	mtr.start();
  	log_ptr = mlog_open(&mtr, 11 + 8);
  	log_ptr = mlog_write_initial_log_record_low(
  		MLOG_INDEX_LOAD,
  		index->table->space->id, index->page, log_ptr, &mtr);
  	mach_write_to_8(log_ptr, index->id);
  	mlog_close(&mtr, log_ptr + 8);
  	mtr.commit();
  }
  
  /** Build indexes on a table by reading a clustered index, creating a temporary
  file containing index entries, merge sorting these index entries and inserting
  sorted index entries to indexes.
  @param[in]	trx		transaction
  @param[in]	old_table	table where rows are read from
  @param[in]	new_table	table where indexes are created; identical to
  old_table unless creating a PRIMARY KEY
  @param[in]	online		true if creating indexes online
  @param[in]	indexes		indexes to be created
  @param[in]	key_numbers	MySQL key numbers
  @param[in]	n_indexes	size of indexes[]
  @param[in,out]	table		MySQL table, for reporting erroneous key value
  if applicable
  @param[in]	defaults	default values of added, changed columns, or NULL
  @param[in]	col_map		mapping of old column numbers to new ones, or
  NULL if old_table == new_table
  @param[in]	add_autoinc	number of added AUTO_INCREMENT columns, or
  ULINT_UNDEFINED if none is added
  @param[in,out]	sequence	autoinc sequence
  @param[in]	skip_pk_sort	whether the new PRIMARY KEY will follow
  existing order
  @param[in,out]	stage		performance schema accounting object, used by
  ALTER TABLE. stage->begin_phase_read_pk() will be called at the beginning of
  this function and it will be passed to other functions for further accounting.
  @param[in]	add_v		new virtual columns added along with indexes
  @param[in]	eval_table	mysql table used to evaluate virtual column
  				value, see innobase_get_computed_value().
  @param[in]	allow_not_null	allow the conversion from null to not-null
  @return DB_SUCCESS or error code */
  dberr_t
  row_merge_build_indexes(
  	trx_t*			trx,
  	dict_table_t*		old_table,
  	dict_table_t*		new_table,
  	bool			online,
  	dict_index_t**		indexes,
  	const ulint*		key_numbers,
  	ulint			n_indexes,
  	struct TABLE*		table,
  	const dtuple_t*		defaults,
  	const ulint*		col_map,
  	ulint			add_autoinc,
  	ib_sequence_t&		sequence,
  	bool			skip_pk_sort,
  	ut_stage_alter_t*	stage,
  	const dict_add_v_col_t*	add_v,
  	struct TABLE*		eval_table,
  	bool			allow_not_null)
  {
  	merge_file_t*		merge_files;
  	row_merge_block_t*	block;
  	ut_new_pfx_t		block_pfx;
  	size_t			block_size;
  	ut_new_pfx_t		crypt_pfx;
  	row_merge_block_t*	crypt_block = NULL;
  	ulint			i;
  	ulint			j;
  	dberr_t			error;
  	pfs_os_file_t		tmpfd = OS_FILE_CLOSED;
  	dict_index_t*		fts_sort_idx = NULL;
  	fts_psort_t*		psort_info = NULL;
  	fts_psort_t*		merge_info = NULL;
  	int64_t			sig_count = 0;
  	bool			fts_psort_initiated = false;
  
  	double total_static_cost = 0;
  	double total_dynamic_cost = 0;
  	ulint total_index_blocks = 0;
  	double pct_cost=0;
  	double pct_progress=0;
  
  	DBUG_ENTER("row_merge_build_indexes");
  
  	ut_ad(!srv_read_only_mode);
  	ut_ad((old_table == new_table) == !col_map);
  	ut_ad(!defaults || col_map);
  
  	stage->begin_phase_read_pk(skip_pk_sort && new_table != old_table
  				   ? n_indexes - 1
  				   : n_indexes);
  
  	/* Allocate memory for merge file data structure and initialize
  	fields */
  
  	ut_allocator<row_merge_block_t>	alloc(mem_key_row_merge_sort);
  
  	/* This will allocate "3 * srv_sort_buf_size" elements of type
  	row_merge_block_t. The latter is defined as byte. */
  	block_size = 3 * srv_sort_buf_size;
  	block = alloc.allocate_large(block_size, &block_pfx);
  
  	if (block == NULL) {
  		DBUG_RETURN(DB_OUT_OF_MEMORY);
  	}
  
  	TRASH_ALLOC(&crypt_pfx, sizeof crypt_pfx);
  
  	if (log_tmp_is_encrypted()) {
  		crypt_block = static_cast<row_merge_block_t*>(
  			alloc.allocate_large(block_size,
  					     &crypt_pfx));
  
  		if (crypt_block == NULL) {
  			DBUG_RETURN(DB_OUT_OF_MEMORY);
  		}
  	}
  
  	trx_start_if_not_started_xa(trx, true);
  
  	/* Check if we need a flush observer to flush dirty pages.
  	Since we disable redo logging in bulk load, so we should flush
  	dirty pages before online log apply, because online log apply enables
  	redo logging(we can do further optimization here).
  	1. online add index: flush dirty pages right before row_log_apply().
  	2. table rebuild: flush dirty pages before row_log_table_apply().
  
  	we use bulk load to create all types of indexes except spatial index,
  	for which redo logging is enabled. If we create only spatial indexes,
  	we don't need to flush dirty pages at all. */
  	bool	need_flush_observer = (old_table != new_table);
  
  	for (i = 0; i < n_indexes; i++) {
  		if (!dict_index_is_spatial(indexes[i])) {
  			need_flush_observer = true;
  		}
  	}
  
  	FlushObserver*	flush_observer = NULL;
  	if (need_flush_observer) {
  		flush_observer = UT_NEW_NOKEY(
  			FlushObserver(new_table->space, trx, stage));
  
  		trx_set_flush_observer(trx, flush_observer);
  	}
  
  	merge_files = static_cast<merge_file_t*>(
  		ut_malloc_nokey(n_indexes * sizeof *merge_files));
  
  	/* Initialize all the merge file descriptors, so that we
  	don't call row_merge_file_destroy() on uninitialized
  	merge file descriptor */
  
  	for (i = 0; i < n_indexes; i++) {
  		merge_files[i].fd = OS_FILE_CLOSED;
  		merge_files[i].offset = 0;
  	}
  
  	total_static_cost = COST_BUILD_INDEX_STATIC * n_indexes + COST_READ_CLUSTERED_INDEX;
  	total_dynamic_cost = COST_BUILD_INDEX_DYNAMIC * n_indexes;
  	for (i = 0; i < n_indexes; i++) {
  		if (indexes[i]->type & DICT_FTS) {
  			ibool	opt_doc_id_size = FALSE;
  
  			/* To build FTS index, we would need to extract
  			doc's word, Doc ID, and word's position, so
  			we need to build a "fts sort index" indexing
  			on above three 'fields' */
  			fts_sort_idx = row_merge_create_fts_sort_index(
  				indexes[i], old_table, &opt_doc_id_size);
  
  			row_merge_dup_t*	dup
  				= static_cast<row_merge_dup_t*>(
  					ut_malloc_nokey(sizeof *dup));
  			dup->index = fts_sort_idx;
  			dup->table = table;
  			dup->col_map = col_map;
  			dup->n_dup = 0;
  
  			/* This can fail e.g. if temporal files can't be
  			created */
  			if (!row_fts_psort_info_init(
  					trx, dup, new_table, opt_doc_id_size,
  					&psort_info, &merge_info)) {
  				error = DB_CORRUPTION;
  				goto func_exit;
  			}
  
  			/* We need to ensure that we free the resources
  			allocated */
  			fts_psort_initiated = true;
  		}
  	}
  
  	if (global_system_variables.log_warnings > 2) {
  		sql_print_information("InnoDB: Online DDL : Start reading"
  				      " clustered index of the table"
  				      " and create temporary files");
  	}
  
  	pct_cost = COST_READ_CLUSTERED_INDEX * 100 / (total_static_cost + total_dynamic_cost);
  
  	/* Do not continue if we can't encrypt table pages */
  	if (!old_table->is_readable() ||
  	    !new_table->is_readable()) {
  		error = DB_DECRYPTION_FAILED;
  		ib_push_warning(trx->mysql_thd, DB_DECRYPTION_FAILED,
  			"Table %s is encrypted but encryption service or"
  			" used key_id is not available. "
  			" Can't continue reading table.",
  			!old_table->is_readable() ? old_table->name.m_name :
  				new_table->name.m_name);
  		goto func_exit;
  	}
  
  	/* Read clustered index of the table and create files for
  	secondary index entries for merge sort */
  	error = row_merge_read_clustered_index(
  		trx, table, old_table, new_table, online, indexes,
  		fts_sort_idx, psort_info, merge_files, key_numbers,
  		n_indexes, defaults, add_v, col_map, add_autoinc,
  		sequence, block, skip_pk_sort, &tmpfd, stage,
  		pct_cost, crypt_block, eval_table, allow_not_null);
  
  	stage->end_phase_read_pk();
  
  	pct_progress += pct_cost;
  
  	if (global_system_variables.log_warnings > 2) {
  		sql_print_information("InnoDB: Online DDL : End of reading "
  				      "clustered index of the table"
  				      " and create temporary files");
  	}
  
  	for (i = 0; i < n_indexes; i++) {
  		total_index_blocks += merge_files[i].offset;
  	}
  
  	if (error != DB_SUCCESS) {
  		goto func_exit;
  	}
  
  	DEBUG_SYNC_C("row_merge_after_scan");
  
  	/* Now we have files containing index entries ready for
  	sorting and inserting. */
  
  	for (i = 0; i < n_indexes; i++) {
  		dict_index_t*	sort_idx = indexes[i];
  
  		if (dict_index_is_spatial(sort_idx)) {
  			continue;
  		}
  
  		if (indexes[i]->type & DICT_FTS) {
  			os_event_t	fts_parallel_merge_event;
  
  			sort_idx = fts_sort_idx;
  
  			fts_parallel_merge_event
  				= merge_info[0].psort_common->merge_event;
  
  			if (FTS_PLL_MERGE) {
  				ulint	trial_count = 0;
  				bool	all_exit = false;
  
  				os_event_reset(fts_parallel_merge_event);
  				row_fts_start_parallel_merge(merge_info);
  wait_again:
  				os_event_wait_time_low(
  					fts_parallel_merge_event, 1000000,
  					sig_count);
  
  				for (j = 0; j < FTS_NUM_AUX_INDEX; j++) {
  					if (merge_info[j].child_status
  					    != FTS_CHILD_COMPLETE
  					    && merge_info[j].child_status
  					    != FTS_CHILD_EXITING) {
  						sig_count = os_event_reset(
  						fts_parallel_merge_event);
  
  						goto wait_again;
  					}
  				}
  
  				/* Now all children should complete, wait
  				a bit until they all finish using event */
  				while (!all_exit && trial_count < 10000) {
  					all_exit = true;
  
  					for (j = 0; j < FTS_NUM_AUX_INDEX;
  					     j++) {
  						if (merge_info[j].child_status
  						    != FTS_CHILD_EXITING) {
  							all_exit = false;
  							os_thread_sleep(1000);
  							break;
  						}
  					}
  					trial_count++;
  				}
  
  				if (!all_exit) {
  					ib::error() << "Not all child merge"
  						" threads exited when creating"
  						" FTS index '"
  						<< indexes[i]->name << "'";
  				} else {
  					for (j = 0; j < FTS_NUM_AUX_INDEX;
  					     j++) {
  
  						os_thread_join(merge_info[j]
  							       .thread_hdl);
  					}
  				}
  			} else {
  				/* This cannot report duplicates; an
  				assertion would fail in that case. */
  				error = row_fts_merge_insert(
  					sort_idx, new_table,
  					psort_info, 0);
  			}
  
  #ifdef FTS_INTERNAL_DIAG_PRINT
  			DEBUG_FTS_SORT_PRINT("FTS_SORT: Complete Insert\n");
  #endif
  		} else if (merge_files[i].fd != OS_FILE_CLOSED) {
  			char	buf[NAME_LEN + 1];
  			row_merge_dup_t	dup = {
  				sort_idx, table, col_map, 0};
  
  			pct_cost = (COST_BUILD_INDEX_STATIC +
  				(total_dynamic_cost * merge_files[i].offset /
  					total_index_blocks)) /
  				(total_static_cost + total_dynamic_cost)
  				* PCT_COST_MERGESORT_INDEX * 100;
  			char*	bufend = innobase_convert_name(
  				buf, sizeof buf,
  				indexes[i]->name,
  				strlen(indexes[i]->name),
  				trx->mysql_thd);
  			buf[bufend - buf]='\0';
  
  			if (global_system_variables.log_warnings > 2) {
  				sql_print_information("InnoDB: Online DDL :"
  						      " Start merge-sorting"
  						      " index %s"
  						      " (" ULINTPF
  						      " / " ULINTPF "),"
  						      " estimated cost :"
  						      " %2.4f",
  						      buf, i + 1, n_indexes,
  						      pct_cost);
  			}
  
  			error = row_merge_sort(
  					trx, &dup, &merge_files[i],
  					block, &tmpfd, true,
  					pct_progress, pct_cost,
  					crypt_block, new_table->space->id,
  					stage);
  
  			pct_progress += pct_cost;
  
  			if (global_system_variables.log_warnings > 2) {
  				sql_print_information("InnoDB: Online DDL :"
  						      " End of "
  						      " merge-sorting index %s"
  						      " (" ULINTPF
  						      " / " ULINTPF ")",
  						      buf, i + 1, n_indexes);
  			}
  
  			DBUG_EXECUTE_IF(
  				"ib_merge_wait_after_sort",
  				os_thread_sleep(20000000););  /* 20 sec */
  
  			if (error == DB_SUCCESS) {
  				BtrBulk	btr_bulk(sort_idx, trx->id,
  						 flush_observer);
  				btr_bulk.init();
  
  				pct_cost = (COST_BUILD_INDEX_STATIC +
  					(total_dynamic_cost * merge_files[i].offset /
  						total_index_blocks)) /
  					(total_static_cost + total_dynamic_cost) *
  					PCT_COST_INSERT_INDEX * 100;
  
  				if (global_system_variables.log_warnings > 2) {
  					sql_print_information(
  						"InnoDB: Online DDL : Start "
  						"building index %s"
  						" (" ULINTPF
  						" / " ULINTPF "), estimated "
  						"cost : %2.4f", buf, i + 1,
  						n_indexes, pct_cost);
  				}
  
  				error = row_merge_insert_index_tuples(
  					sort_idx, old_table,
  					merge_files[i].fd, block, NULL,
  					&btr_bulk,
  					merge_files[i].n_rec, pct_progress, pct_cost,
  					crypt_block, new_table->space->id,
  					stage);
  
  				error = btr_bulk.finish(error);
  
  				pct_progress += pct_cost;
  
  				if (global_system_variables.log_warnings > 2) {
  					sql_print_information(
  						"InnoDB: Online DDL : "
  						"End of building index %s"
  						" (" ULINTPF " / " ULINTPF ")",
  						buf, i + 1, n_indexes);
  				}
  			}
  		}
  
  		/* Close the temporary file to free up space. */
  		row_merge_file_destroy(&merge_files[i]);
  
  		if (indexes[i]->type & DICT_FTS) {
  			row_fts_psort_info_destroy(psort_info, merge_info);
  			fts_psort_initiated = false;
  		} else if (error != DB_SUCCESS || !online) {
  			/* Do not apply any online log. */
  		} else if (old_table != new_table) {
  			ut_ad(!sort_idx->online_log);
  			ut_ad(sort_idx->online_status
  			      == ONLINE_INDEX_COMPLETE);
  		} else {
  			ut_ad(need_flush_observer);
  			if (global_system_variables.log_warnings > 2) {
  				sql_print_information(
  					"InnoDB: Online DDL : Applying"
  					" log to index");
  			}
  			flush_observer->flush();
  			row_merge_write_redo(indexes[i]);
  
  			DEBUG_SYNC_C("row_log_apply_before");
  			error = row_log_apply(trx, sort_idx, table, stage);
  			DEBUG_SYNC_C("row_log_apply_after");
  		}
  
  		if (error != DB_SUCCESS) {
  			trx->error_key_num = key_numbers[i];
  			goto func_exit;
  		}
  
  		if (indexes[i]->type & DICT_FTS && fts_enable_diag_print) {
  			ib::info() << "Finished building full-text index "
  				<< indexes[i]->name;
  		}
  	}
  
  func_exit:
  
  	DBUG_EXECUTE_IF(
  		"ib_build_indexes_too_many_concurrent_trxs",
  		error = DB_TOO_MANY_CONCURRENT_TRXS;
  		trx->error_state = error;);
  
  	if (fts_psort_initiated) {
  		/* Clean up FTS psort related resource */
  		row_fts_psort_info_destroy(psort_info, merge_info);
  		fts_psort_initiated = false;
  	}
  
  	row_merge_file_destroy_low(tmpfd);
  
  	for (i = 0; i < n_indexes; i++) {
  		row_merge_file_destroy(&merge_files[i]);
  	}
  
  	if (fts_sort_idx) {
  		dict_mem_index_free(fts_sort_idx);
  	}
  
  	ut_free(merge_files);
  
  	alloc.deallocate_large(block, &block_pfx, block_size);
  
  	if (crypt_block) {
  		alloc.deallocate_large(crypt_block, &crypt_pfx, block_size);
  	}
  
  	DICT_TF2_FLAG_UNSET(new_table, DICT_TF2_FTS_ADD_DOC_ID);
  
  	if (online && old_table == new_table && error != DB_SUCCESS) {
  		/* On error, flag all online secondary index creation
  		as aborted. */
  		for (i = 0; i < n_indexes; i++) {
  			ut_ad(!(indexes[i]->type & DICT_FTS));
  			ut_ad(!indexes[i]->is_committed());
  			ut_ad(!dict_index_is_clust(indexes[i]));
  
  			/* Completed indexes should be dropped as
  			well, and indexes whose creation was aborted
  			should be dropped from the persistent
  			storage. However, at this point we can only
  			set some flags in the not-yet-published
  			indexes. These indexes will be dropped later
  			in row_merge_drop_indexes(), called by
  			rollback_inplace_alter_table(). */
  
  			switch (dict_index_get_online_status(indexes[i])) {
  			case ONLINE_INDEX_COMPLETE:
  				break;
  			case ONLINE_INDEX_CREATION:
  				rw_lock_x_lock(
  					dict_index_get_lock(indexes[i]));
  				row_log_abort_sec(indexes[i]);
  				indexes[i]->type |= DICT_CORRUPT;
  				rw_lock_x_unlock(
  					dict_index_get_lock(indexes[i]));
  				new_table->drop_aborted = TRUE;
  				/* fall through */
  			case ONLINE_INDEX_ABORTED_DROPPED:
  			case ONLINE_INDEX_ABORTED:
  				MONITOR_ATOMIC_INC(
  					MONITOR_BACKGROUND_DROP_INDEX);
  			}
  		}
  	}
  
  	DBUG_EXECUTE_IF("ib_index_crash_after_bulk_load", DBUG_SUICIDE(););
  
  	if (flush_observer != NULL) {
  		ut_ad(need_flush_observer);
  
  		DBUG_EXECUTE_IF("ib_index_build_fail_before_flush",
  			error = DB_INTERRUPTED;
  		);
  
  		if (error != DB_SUCCESS) {
  			flush_observer->interrupted();
  		}
  
  		flush_observer->flush();
  
  		UT_DELETE(flush_observer);
  
  		if (trx_is_interrupted(trx)) {
  			error = DB_INTERRUPTED;
  		}
  
  		if (error == DB_SUCCESS && old_table != new_table) {
  			for (const dict_index_t* index
  				     = dict_table_get_first_index(new_table);
  			     index != NULL;
  			     index = dict_table_get_next_index(index)) {
  				row_merge_write_redo(index);
  			}
  		}
  	}
  
  	DBUG_RETURN(error);
  }
  